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My keto breakfast casserole is loaded with sausage, cheese, and low-carb veggies and makes the perfect savory breakfast. It’s easy to make ahead, super customizable, and freezes really well, too. Prep some for your weekend breakfast or part of a meal prep.
Table of Contents
This keto breakfast casserole is one of those easy recipes I turn to when I want something savory, high-protein, and super filling. Adding cottage cheese and shredded cheese melts into the eggs, making it creamy, fluffy, and soft. I like adding some sausage for extra protein and delicious flavor, and the onions and peppers add color and nutrients. My secret addition is some pre-cooked cauliflower, which adds extra bulk, similar to what potatoes would add, and completes the dish.
Why you’ll love my keto breakfast casserole
- High-protein: This dish includes eggs, cottage cheese, sausage, and shredded cheese. Each serving packs a whopping 45 grams of protein.
- Easy to customize: I like to use whatever leftover veggies or bits and bobs I have in the fridge, but you can customize this casserole however you like. I’ll give you plenty of suggestions, too.
- Makes great meal prep: This casserole freezes like a dream and doesn’t get rubbery when reheated, making it a great grab-and-go brekky during the week.
- Minimal cleanup: Everything is baked in one dish, so there is barely any clean-up once cooked.
Key Ingredients
- Eggs and egg whites. I used a mixture so you get the richness of whole eggs but with few carbs, but you can use all whole eggs if you prefer.
- Cauliflower. Any cooked cauliflower is fine. I typically microwave some frozen cauliflower, but you can whip up my air fryer cauliflower if you want something with a little more flavor.
- Onions and peppers. Finely chopped.
- Sausage. I typically use chopped Italian sausage, but any sausage works, including homemade ones like chopped up turkey sausage or chicken sausage.
- Cottage cheese. Adds creaminess and richness to the casserole without excess calories. Opt for full-fat cottage cheese, which contains fewer carbs than low-fat or fat-free varieties.
- Cheddar cheese. Shredded cheese to mix through and on top of the casserole.
How to make keto breakfast casserole
This is an overview with step-by-step photos. Full ingredients & instructions are in the recipe card below.
Step 1- Saute the onions, pepper, and sausage until tender.
Step 2- Transfer into a casserole or baking dish, along with the cauliflower. Ensure they are spread out in an even layer.
Step 3- Whisk the eggs, cottage cheese, cheddar cheese, and seasonings.
Step 4- Pour the egg mixture into the casserole dish. Ensure it covers the entire dish.
Step 5- Bake for 40 minutes or until golden brown and the middle is set.
Pro tips for making the best breakfast casserole
- Grease up. Grease your baking dish generously to prevent the egg and vegetable mixture from sticking to it.
- Drain excess moisture. Onions and peppers don’t usually add much moisture once sauteed, but in case it does for you, soak up the excess moisture before adding it to the casserole dish. We don’t want a watery casserole.
- Cover the casserole with foil. If the top of the casserole begins to brown before it’s fully cooked, lightly cover it with aluminum foil to prevent burning.
- For a thicker casserole, you can add one tablespoon of almond flour or coconut flour. Be sure to whisk it well into the assembled casserole to prevent it from clumping.
- Let it rest after cooking. Once it has baked, I like to let the casserole sit for about ten minutes so that it has time to firm up before slicing.
Storage and make-ahead tips
To store: Leftovers can be stored in the refrigerator, covered. It will keep well for up to 1 week.
Make ahead: I sometimes assemble the casserole in the fridge the night before. The next morning, I bake it straight from the refrigerator. I do suggest adding an extra ten minutes of cooking time to compensate.
Keto Breakfast Casserole
Video
Ingredients
- 1 pound cauliflower cooked * See notes
- 1 large bell pepper chopped
- 1 large onion chopped
- 1/4 pound Italian sausage chopped
- 6 large eggs
- 4 large egg whites or extra eggs
- 1 cup cottage cheese
- 1 1/2 cups shredded cheese Mozzarella or cheddar
- 1 teaspoon salt
- 1 teaspoon pepper
Instructions
- Preheat the oven to 180C/350F. Grease a 9 x 13-inch baking dish and set aside.
- In a large skillet, add the oil and place over medium heat. Once hot, add the onions, peppers, and Italian sausage. Cook for 3-4 minutes, until the sausage is browned.
- Placed the cauliflower, vegetables, and sausage into the baking dish. Spread out in an even layer.
- In a mixing bowl, whisk together the eggs, egg whites, cottage cheese, shredded cheese, salt, and pepper. Pour the mixture into the baking dish.
- Bake the casserole for 35-40 minutes, or until the center is cooked and the edges are golden brown.
- Remove the casserole from the oven and serve immediately, or let it cool completely.
Notes
- Make egg muffins. When I’m hosting, I sometimes like to make mini egg casseroles. To do this, grease a muffin tin, pour the egg mixture into the tins, and bake for 25-30 minutes or until a toothpick inserted comes out clean.
- Veggies. Like spinach, mushrooms, diced tomatoes, or green onions. Just make sure whatever veggies you add are sliced and cooked before adding to the egg mixture.
- Protein. Stir in cooked bacon, diced ham, smoked salmon, or ground pork.
- Seasonings. Like garlic powder, onion powder, or if you can handle the heat, a few dashes of hot sauce.
- Storage. Leftovers keep in the fridge for up to one week for up to 6 months in the freeze. Reheat in the microwave or thaw to room temperature.
Nutrition
Frequently asked questions
If there is excess moisture from the cauliflower, onion, or peppers, you risk adding excess moisture to the casserole,, turning it watery. Soak up all moisture before assembling in the casserole dish to prevent this.
Yes, you can. Slice the casserole into portions and place in an airtight container and store in the freezer for up to 6 months.
This I showed to my mum and she immediately said she will prepare when I visit her. I am excited.
Italian sausage? What is the difference between this and usual?
Excellent. 5 star. I’ve made this for years and I love it
We loved this breakfast casserole! I didn’t have cauliflower on hand, so I used up leftover bell peppers, spinach, and onions. I added 1/2 teaspoon of dry mustard and paprika per preference, and this has made it into our “top 10” list!
I’m making your cheesy bread tonight…another favorite!
Looking forward to trying this
Brand new to Keto, and love your Keto recipes. I’ve made this and love it, I’ll make this a bunch a times.
😀 Love to hear that!
I love cauliflower, but it hates me. 🙁 Can I skip it without ruining the recipe or do I need a filler to replace it.
Sure! just use your favorite vegetables!
So if I rather use the whole eggs, I just use 10 instead of 6 whole and 4 egg whites? I know that seems like a “stupid” question, but just want to verify before I make it. Looks so good!
Not a stupid question at all! I’d go with 9 eggs.
How many servings are in this?
This is great and so straight forward.
Can you consider adding the option for metric, so non Americans can easily use the ingredients too.
Hi there! We have kitchen conversion tools you can use like this https://thebigmansworld.com/how-many-grams-in-a-cup/
Can’t wait to try this! Looks so yummy …me too prefer savory than sweet breakfast. Question: the frozen cauliflower is it floret or rice?
Either works, I like the florets for the chunks 🙂
Can’t wait to make this!
A question though — Can this recipe be put together the night before and refrigerated overnight – then bake in the am???
Yes 🙂 I actually like it like that as it softens the cauliflower!
This casserole looks so delicious! I can hardly wait to make it ♥
Perfect!
This looks delicious! Can’t wait to make it!