Low Carb Breakfast Casserole with Bacon + Zucchini

This low carb breakfast casserole is made with bacon, zucchini, onions and cheese! It’s easy to make and makes for easy breakfasts during the week. Just reheat and eat. Top with homemade ranch dressing and roasted tomatoes for an extra burst of flavor!

How was your weekend? I hope it was great! Mine was. First, it was a three day weekend for me because I had Memorial Day off. Since Ken had it off too we went to our place in Lakeland on Friday and came back on Monday. In addition to enjoying three days off from work, we enjoyed time with family during a family dinner Sunday evening. I made brownies and street corn salad for the family dinner. The street corn salad was incredibly good so I might share the recipe on my blog one day. Our guests brought over fried chicken, deviled eggs, salad and cheesecake! I don’t eat fried chicken or cheesecake often so both were definitely a delicious treat!

RECIPE INSPIRATION AND INFO

Inspiration for this low carb breakfast casserole comes from my love for quiches. Quiches are quite fantastic but lately I am shying away from flour crusts and I am limiting my carb intake. In fact, I haven’t had a “regular” quiche in quite some time!

Frittatas are a great low carb option that that are easy to make. This low carb breakfast casserole is similar to a frittata in taste and texture; however, the cooking method differs. For example, a frittata is typically cooked in a skillet on the stovetop over low heat. My low carb breakfast quiche is baked in a round baking pan at 375 degrees for 30 minutes. The baking method eliminates the need to be a frittata watchdog AKA standing over the stove watching it cook.

I used pastured bacon and veggies from the farmers market in this low carb casserole. It’s packed with zucchini, onions and green onions. In addition, cottage cheese and full fat sour cream give the casserole a fluffy texture and creamy taste.

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Why This Low Carb Breakfast Casserole Recipe Works

Breakfast casseroles have been a staple at Southern gatherings for generations. Traditionally, they’re loaded with bread or potatoes to soak up the egg mixture, making them hearty and filling. They are a wonderful way to feed a crowd with minimal morning fuss. You can assemble them the night before and just pop them in the oven when you wake up. It’s easy to see why they’ve remained so popular for family breakfasts, holidays, and church potlucks.

With more folks looking for healthier options, the Low Carb Breakfast Casserole emerged as a modern classic. By ditching the starchy fillers, you’re left with a protein packed, vegetable forward dish that’s just as satisfying. However, this switch can sometimes cause problems. Without the bread or potatoes to act as a binder, some recipes can turn out watery from the vegetables or have a rubbery, overcooked egg texture. No thank you.

That’s where my special twist comes in and why this particular recipe works so well. The secret is the combination of full fat cottage cheese and sour cream in the egg custard. This duo is a game changer. The sour cream adds a beautiful tangy richness and a velvety texture that you just can’t get from milk or cream alone. The cottage cheese melts into the custard as it bakes, adding incredible moisture and an extra boost of protein without affecting the flavor negatively. You won’t even notice it’s there, texturally.

This creamy base protects the eggs, ensuring they bake up fluffy and custardy, never dry. We also take the extra step of sautéing the zucchini in bacon fat first. This not only adds a tremendous amount of savory flavor but also cooks off the excess water from the zucchini, which is the number one cause of a soggy casserole. It’s a simple technique that makes all the difference, guaranteeing a perfect slice every single time.

I topped my slices of low carb breakfast casserole with roasted tomatoes and homemade ranch dressing. Yum factor increased x 1000. ♥︎

Ingredients for Low Carb Breakfast Casserole

The beauty of this recipe is its simplicity. We’re using a handful of fresh, flavorful ingredients to create something truly special. The quality of these items really shines through, so I always recommend getting the best you can find. Here’s what you’ll need to have on hand.

• 2 slices uncooked bacon (I always use uncured bacon to avoid nitrates, and a good thick cut variety will give you more to chop up.)
• 2 C diced zucchini (Smaller, firm zucchini have less water content and more flavor, which is ideal for this casserole.)
• 1 small sweet onion, sliced thin (A Vidalia or other sweet onion adds a lovely, subtle sweetness that complements the salty bacon.)
• 2 tbsp chopped green onion (For a little pop of fresh, mild onion flavor.)
• 6 large eggs (The difference between standard eggs and farm fresh or pasture raised eggs like Vital Farms is huge. The yolks are richer and the color is a beautiful deep orange.)
• 1/2 C full fat cottage cheese (This is part of my secret! Don’t use low fat here. The full fat version is key for creaminess and preventing a watery result.)
• 1/2 C full fat sour cream (And here’s the other part of the magic duo. Full fat sour cream adds a wonderful tang and richness that makes the custard base so luxurious.)
• Sea salt or kosher salt and pepper to taste (Always season as you go!)

The real stars here are the full fat cottage cheese and sour cream. While it might sound a little unusual to put cottage cheese in a breakfast casserole, I promise you it’s the key to the best texture you’ve ever had. It blends seamlessly into the eggs, creating a moisture-rich custard that keeps everything tender and delicious. Paired with the tang from the sour cream, it creates a flavor foundation that is simply irresistible and far more complex than just using milk or cream. This combination is what elevates the dish from a simple egg bake to a truly impressive brunch centerpiece.

Step-by-Step Instructions For Making Low Carb Breakfast Casserole

This casserole comes together in just a few simple stages. By taking a little care with each step, you’ll ensure your final dish is perfectly cooked, full of flavor, and has a wonderfully fluffy, custardy texture. Let’s get cooking!

Step 1: Prep Your Oven and Bacon

First things first, get your oven preheating to 375 degrees. You want it nice and hot when the casserole goes in. While it’s heating, grab a large skillet, preferably cast iron for its even heat distribution, and place it over medium high heat. Lay your bacon slices in the skillet and cook them until they’re perfectly crisp. This usually takes about 5 to 7 minutes. Once cooked, use tongs to remove the bacon and place it on a plate lined with a paper towel to drain. But whatever you do, do not discard that glorious bacon fat in the skillet. That’s liquid gold, and we’re going to use it!

Step 2: Sauté the Vegetables

With the bacon fat still shimmering in the skillet, add your thinly sliced sweet onion, chopped green onion, and diced zucchini. Sauté everything for about 5 to 7 minutes. The goal here is to get the vegetables tender, but not mushy. You still want a little bit of bite in the zucchini. This step is so important because it not only infuses the vegetables with that amazing smoky bacon flavor, but it also cooks off the excess moisture from the zucchini. This is the key to preventing a watery casserole later on. Once they’re tender-crisp, turn off the heat and remove the skillet from the burner.

Step 3: Assemble the Base

While your veggies are cooking, take that crispy bacon and give it a rough chop. Once the skillet is off the heat, stir the chopped bacon right into the zucchini and onion mixture. Now, pour this entire delicious mixture into a 9 inch baking pan. A non-stick pan is great, but a glass or ceramic pie plate works beautifully too. If your pan isn’t non-stick, just give it a quick grease with a little butter or olive oil to prevent sticking.

Step 4: Create the Creamy Egg Custard

In a medium sized mixing bowl, crack your six large eggs. Add the full fat cottage cheese, full fat sour cream, and a generous pinch of sea salt and freshly ground black pepper. Now, whisk it all together until it’s well combined. You want the mixture to be mostly smooth, but don’t worry if there are still a few small cottage cheese curds visible. Those little bits will melt into the casserole, creating wonderful little pockets of creamy texture. This rich custard is the heart of our Low Carb Breakfast Casserole.

Step 5: Combine and Bake

Gently pour your egg custard mixture over the vegetables and bacon in the baking pan. Use a spoon or spatula to give it a gentle stir, just enough to make sure everything is evenly distributed throughout the dish. Place the pan in your preheated 375 degree oven and bake for 30 minutes. You’ll know it’s done when the casserole is puffed up, golden brown around the edges, and the center is set. If you gently jiggle the pan, the middle shouldn’t wobble.

Step 6: Let It Rest

This might be the hardest step, but it’s so important! Once you pull the casserole out of the oven, let it cool on a wire rack for at least 10 minutes before you even think about slicing it. This resting period allows the custard to fully set, which makes for clean, beautiful slices. If you cut into it too soon, it might be a bit soft and fall apart. Patience here will be rewarded, I promise!

How To Serve Low Carb Breakfast Casserole

This casserole is a true delight served warm right out of the oven after its brief rest. It’s a complete meal on its own, packed with protein and veggies, making it a perfect quick breakfast on a busy weekday. But for a weekend brunch or a special occasion, it’s fun to dress it up a bit with some simple and fresh accompaniments. The creamy, savory flavor of the casserole pairs wonderfully with a variety of toppings and side dishes.

Thinking about what to serve alongside this dish is half the fun. You can keep it simple or create a beautiful brunch spread. Here are a few of my favorite ways to serve this versatile Low Carb Breakfast Casserole:

• Add Some Freshness: A few slices of ripe avocado or a dollop of fresh guacamole on top adds a lovely creamy texture and healthy fats that complement the eggs perfectly. A simple spoonful of pico de gallo or your favorite salsa can also add a bright, zesty kick.
• A Touch of Green: For a more complete brunch plate, serve a slice of the casserole next to a simple side salad of mixed greens tossed in a light vinaigrette. The acidity of the dressing cuts through the richness of the casserole beautifully.
• For Spice Lovers: A drizzle of your favorite hot sauce is a fantastic way to add a little heat. I’m partial to Cholula or a good chipotle based hot sauce for a smoky flavor that goes so well with the bacon and eggs.
• Keep it Fruity: To balance the savory notes, a side of fresh berries, like raspberries, blueberries, and strawberries, provides a light and sweet contrast. It makes the whole meal feel extra special and vibrant.

Ultimately, there’s no wrong way to serve this dish. Whether you’re grabbing a slice as you run out the door or sitting down for a leisurely meal with family, these serving suggestions can help you tailor it to any occasion. It’s all about creating a balanced and delicious plate that you’ll absolutely love.

How To Store & Reuse Low Carb Breakfast Casserole Leftovers

One of the best things about this Low Carb Breakfast Casserole is that it’s fantastic for meal prep. I often make one on Sunday to have an easy, grab and go breakfast ready for the first few days of the week. It reheats beautifully, which is not something you can say about all egg dishes. Storing it properly is key to making sure your leftovers taste just as good as they did on day one.

Leftovers are a gift, and this casserole is no exception. Whether you’re packing it for lunch or enjoying it for breakfast again, here’s how to best handle storing and reheating your delicious creation:

• Storing in the Refrigerator: Once the casserole has cooled completely, you can store it in the refrigerator. I find it’s best to cut it into individual slices before storing. Place the slices in an airtight container. They will stay fresh and delicious for up to 4 days. Storing them pre sliced makes reheating a single portion quick and easy.
• Reheating for Best Results: While you can certainly use a microwave, my preferred method is the oven or a toaster oven. Place a slice on a baking sheet and heat at 350°F for about 10-15 minutes, or until warmed through. This helps the eggs stay tender and avoids that rubbery texture the microwave can sometimes create. An air fryer also works wonders, heating a slice in just 3-4 minutes at 350°F and giving the edges a lovely little crisp.
• Freezing for Later: Yes, this casserole freezes wonderfully! For the best results, wrap individual slices tightly in plastic wrap and then a layer of aluminum foil. Place the wrapped slices in a freezer-safe zip-top bag. They can be frozen for up to 3 months. To enjoy, just thaw a slice in the refrigerator overnight and then reheat using one of the methods above.

Having these tasty slices ready to go in the fridge or freezer is a lifesaver on busy mornings. It’s a healthy, satisfying meal that’s ready in minutes, saving you from the temptation of less healthy convenience foods. Proper storage ensures you can enjoy your delicious handiwork all week long.

Substitutions & Variations For Low Carb Breakfast Casserole

While I believe this recipe is pretty perfect as is, I’m also a big believer in using what you have and making a recipe your own. This Low Carb Breakfast Casserole is incredibly forgiving and serves as a fantastic base for all sorts of creative variations. Don’t be afraid to experiment with different proteins, vegetables, and cheeses to find your family’s favorite combination. It’s a great way to clean out the vegetable drawer!

Think of this recipe as a template for deliciousness. As long as you keep the egg and dairy ratio the same, you can swap in many different ingredients with great success. Here are some of my favorite substitutions and additions:

• Protein Swaps: Not a bacon fan? No problem! Substitute the bacon with 1/2 pound of cooked and crumbled breakfast sausage, diced ham, or even shredded cooked chicken. For a vegetarian option, simply omit the bacon and sauté the vegetables in a tablespoon of olive oil or butter instead.
• Vegetable Variations: This casserole is a dream for using up whatever veggies you have on hand. Try swapping the zucchini for finely chopped broccoli or cauliflower florets, sliced mushrooms, or diced bell peppers. If you use spinach or another leafy green, be sure to cook it down and squeeze out all the excess water before adding it to the casserole.
• Add Some Cheese: If you want an even richer dish, feel free to add about 1 cup of shredded cheese. A sharp cheddar, Monterey Jack, Gruyère, or even crumbled feta would be divine. You can mix it right into the egg custard or just sprinkle it over the top before baking.
• Dairy Adjustments: If you don’t have sour cream, full fat plain Greek yogurt is an excellent substitute that will provide a similar tang and creaminess. For those avoiding dairy, you can try using a dairy-free sour cream alternative and a dairy-free cottage cheese, though textures may vary slightly.

The possibilities are truly endless. You could add some jalapeños for a spicy kick, or fresh herbs like dill or chives to the egg mixture for a burst of freshness. Have fun with it and let me know in the comments what delicious combinations you come up with!

Low Carb Breakfast Casserole with Bacon and Zucchini

Prep Time: 10 minutes

Cook Time: 30 minutes

This low carb breakfast casserole is made with bacon, zucchini, onions and cheese! It's easy to make and makes for easy breakfasts during the week. Just reheat and eat. Top with homemade ranch dressing and roasted tomatoes for an extra burst of flavor!

Print

Ingredients

• 2 slices uncooked bacon (I always use uncured)
• 2 C diced zucchini
• 1 small sweet onion, sliced thin
• 2 tbsp chopped green onion
• 6 large eggs (my favs are farm fresh or Vital Farms eggs)
• 1/2 C full fat cottage cheese
• 1/2 C full fat sour cream
• Sea salt or kosher salt and pepper to taste

Instructions

1. Preheat oven to 375 degrees.
2. Cook the bacon in a skillet over medium high heat. After the bacon is done cooking remove it from the skillet and place on a paper towel lined plate. Reserve the bacon fat.
3. Place the sweet onion, green onion and zucchini into the skillet with the bacon fat. Cook for 5-7 minutes or until tender. Do not overcook - you don't want mushy zucchini!
4. Meanwhile, chop the bacon.
5. After the veggies are done cooking turn off the heat and remove the skillet from the heat. Mix the chopped bacon into the zucchini/onion mixture and pour into a 9 inch non-stick baking pan. If your pan isn't non-stick, grease it with butter or olive oil.
6. Whisk together the egg, cottage cheese, sour cream and salt and pepper to taste. Pour the mixture into the baking pan over the zucchini/onion mixture. Mix together to incorporate and evenly distribute the zucchini/onion mixture.
7. Bake at 375 degrees for 30 minutes.
8. Cool for 10 minutes and then slice into 6 equal slices.

Notes

NUTRITION: Calories: 173; Fat: 10g; Carb: 9g; Dietary Fiber: 2g; Net Carb: 7g; Protein: 11gNutrition information calculated using My Fitness Pal and is an estimate. These calculations include the broccoli. Here is a link to the recipe in My Fitness Pal for your reference. Low Barb Breakfast Casserole.

5 FAQs About Low Carb Breakfast Casserole

Here are some straightforward answers to the most common questions I receive about this low carb breakfast casserole recipe.

Why is my low carb breakfast casserole watery?

A watery casserole is the most common frustration, but it’s completely avoidable! There are typically two culprits behind this issue. The first and most likely reason is the water content in your vegetables. Vegetables like zucchini, mushrooms, and spinach are full of water, which they release during the baking process. If you add them to the casserole raw, that water will seep out and create a soggy, soupy mess at the bottom of your dish.

That’s why the step of sautéing the vegetables first is so crucial in my recipe. By cooking the zucchini and onions in the skillet before they go into the baking pan, you’re cooking off a significant amount of that excess moisture. The second cause can be the dairy you use. Using low fat or fat free cottage cheese and sour cream can contribute to a watery result, as they contain more water and stabilizers than their full fat counterparts. Stick with full fat dairy and always pre-cook your high moisture veggies, and you’ll have a perfectly set, sliceable casserole every time.

Can I make this low carb breakfast casserole ahead of time?

Absolutely! This recipe is a fantastic make ahead option, which is why it’s so perfect for holidays, entertaining, or just busy weekday mornings. You have two excellent options. The first is to fully bake the casserole as directed, let it cool completely, then cover it tightly and store it in the refrigerator for up to 3 days. When you’re ready to serve, you can either warm the entire casserole in a 350°F oven until heated through, or simply reheat individual slices as needed.

Your second option is to assemble the casserole without baking it. You can prepare the vegetable and bacon mixture and place it in the baking dish. Then, in a separate bowl, whisk together the egg custard. Store both components, covered, in the refrigerator overnight. In the morning, just give the egg mixture a quick re-whisk, pour it over the vegetables, and bake as directed. You may need to add 5 to 10 minutes to the baking time since you’re starting with a cold dish.

What makes this breakfast casserole low carb?

This breakfast casserole is considered low carb because it intentionally omits the high carbohydrate ingredients that are found in most traditional breakfast casserole recipes. Classic casseroles almost always include a starchy base like cubed bread, hash brown potatoes, or even tater tots. These ingredients act as a filler and help soak up the egg mixture, but they also add a significant amount of carbohydrates to the dish.

My recipe skips those starches entirely. Instead, the bulk of the casserole comes from ingredients that are naturally low in carbs: eggs, bacon, cheese, and low starch vegetables like zucchini and onions. The result is a dish that is high in protein and healthy fats, which keeps you feeling full and satisfied for hours without causing a spike in blood sugar. With only 7 grams of net carbs per serving, it’s a perfect fit for a low carb, keto, or gluten free lifestyle.

Is cottage cheese good in a breakfast casserole?

I know it might sound a little unconventional, but trust me on this, cottage cheese is a secret weapon in breakfast casseroles! It is an absolutely fantastic addition. When you whisk it into the eggs with the sour cream, it breaks down and melts into the custard as it bakes. You won’t find any big, lumpy curds in the final product. Instead, it creates a wonderfully moist, tender, and almost souffle-like texture that’s hard to achieve with milk or cream alone.

Beyond the amazing texture, cottage cheese also provides two other great benefits. First, it adds a subtle tangy flavor that complements the richness of the eggs and bacon. Second, it significantly boosts the protein content of the casserole. This extra protein makes each slice more filling and nutritionally dense, so a small serving is enough to keep you satisfied all morning. Once you try it, you may never go back to making an egg casserole without it.

How do I know when my low carb breakfast casserole is fully cooked?

Knowing when an egg dish is perfectly cooked can be tricky, as undercooked is unappetizing and overcooked can be rubbery. For this Low Carb Breakfast Casserole, there are several visual and physical cues to look for. First, look at the appearance. The casserole should be puffed up, especially around the edges, and the top should be a beautiful golden brown color. The edges might even be slightly pulled away from the sides of the pan.

Next, give the pan a gentle shake. The center of the casserole should be firm and not jiggle. If the middle still looks wet or wobbles significantly, it needs more time in the oven. For the most foolproof method, use the classic knife test. Insert a thin knife or a toothpick into the very center of the casserole. If it comes out clean, with no wet egg batter clinging to it, the casserole is done. For those who like to be precise, the internal temperature should be between 160°F and 165°F when checked with an instant read thermometer.

Try These Recipes Next

If you loved the ease and flavor of this simple breakfast casserole, I have a few other morning favorites I think you’ll enjoy.

• Low Carb Breakfast Skillet: A quick, one-pan meal full of savory sausage and veggies that’s perfect for any day of the week.
• Breakfast Egg Bake Casserole: Another crowd pleasing casserole, this one features a delicious blend of ham, cheese, and spinach.
• Crustless Sausage and Veggie Quiche: All the rich, decadent flavor of a classic quiche without any of the fuss of making a crust.

Each one is a simple, satisfying way to start your day off on a delicious note.

Did you make this recipe? I’d love for you to leave a comment and a rating below! 

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