This easy keto breakfast casserole is a hearty, cheesy breakfast made with eggs, breakfast sausage, crispy bacon, spinach, and plenty of melted cheddar cheese.
Everything comes together in one baking dish, making this a convenient breakfast for busy mornings, weekend brunch, or meal prep.
The eggs bake until tender and fluffy while the sausage, bacon, spinach, and cheese add plenty of savory flavor. You can prepare the casserole ahead of time and simply slice and reheat it throughout the week.
Why You’ll Love This Easy Keto Breakfast Casserole
- Easy one-dish breakfast
- Low-carb ingredients
- High in protein
- Great for meal prep
- Make-ahead friendly
- Family-friendly
- Cheesy and flavorful
- Perfect for weekend brunch
- Easy to customize
- Delicious leftovers
Ingredients
For the Casserole
- 10 large eggs
- 1/2 cup heavy cream
- 1 pound breakfast sausage
- 6 slices bacon
- 2 cups fresh baby spinach
- 1/2 small yellow onion, finely diced
- 1 cup shredded sharp cheddar cheese
- 1/2 cup shredded Monterey Jack cheese
- 1/4 cup grated Parmesan cheese
- 1/2 teaspoon garlic powder
- 1/2 teaspoon paprika
- 1/2 teaspoon salt
- 1/4 teaspoon black pepper
- 1 tablespoon butter or olive oil
Optional Toppings
- Fresh chopped parsley
- Sliced green onions
- Extra shredded cheese
- Diced avocado
- Hot sauce
How to Make Easy Keto Breakfast Casserole
1. Preheat the Oven
Preheat your oven to 375°F.
Lightly grease a 9×13-inch baking dish with butter or olive oil.
2. Cook the Bacon
Place the bacon in a large skillet over medium heat.
Cook until crisp.
Transfer the bacon to a paper towel-lined plate.
Once cool enough to handle, crumble or chop the bacon into small pieces.
Reserve about 1 tablespoon of the bacon fat in the skillet.
3. Cook the Sausage
Add the breakfast sausage to the same skillet.
Cook over medium heat while breaking it into small pieces.
Continue cooking until browned and fully cooked.
4. Add the Onion
Add the diced onion to the skillet.
Cook for about 3–4 minutes until softened.
5. Add the Spinach
Add the fresh spinach.
Cook for 1–2 minutes, stirring gently, until the spinach wilts.
Remove the skillet from the heat.
6. Prepare the Egg Mixture
Crack the eggs into a large mixing bowl.
Add the heavy cream, garlic powder, paprika, salt, and black pepper.
Whisk until the eggs and cream are fully combined.
Don’t over-whisk; a smooth mixture is enough.
7. Add the Cheese
Stir about half of the cheddar, Monterey Jack, and Parmesan into the egg mixture.
Reserve the remaining cheese for the top.
8. Assemble the Casserole
Spread the cooked sausage, onion, spinach, and crumbled bacon evenly across the bottom of the prepared baking dish.
Pour the egg mixture over the top.
Gently shake the baking dish so the egg mixture settles around the filling.
9. Add the Cheese Topping
Sprinkle the remaining cheddar, Monterey Jack, and Parmesan evenly over the casserole.
Make sure the cheese covers the surface without creating an overly thick layer.
10. Bake
Place the casserole in the preheated oven.
Bake for approximately 30–40 minutes, or until the center is set and the top is lightly golden.
The casserole should be firm around the edges and slightly springy in the center.
11. Rest
Remove the casserole from the oven.
Allow it to rest for approximately 10 minutes before slicing.
This helps the eggs finish setting and makes the casserole easier to serve.
12. Garnish and Serve
Sprinkle fresh parsley or sliced green onions over the top.
Add diced avocado or hot sauce if desired.
Slice into squares and serve warm.
How Do I Know When the Casserole Is Done?
The edges should be firm and lightly golden.
The center should no longer look liquid but should still have a slightly soft, springy texture.
Avoid overbaking because eggs can become dry and rubbery.
Can I Make This Casserole Ahead of Time?
Yes.
This is one of the best features of the recipe.
You can assemble the casserole the night before, cover it tightly, and refrigerate it.
Bake it the next morning.
Because the casserole starts cold, it may require a few additional minutes in the oven.
Can I Use Different Breakfast Meat?
Absolutely.
Try:
- Turkey sausage
- Chicken sausage
- Ham
- Cooked bacon
- Diced leftover steak
- Ground beef
Make sure any meat added to the casserole is fully cooked before assembly.
Can I Use Frozen Spinach?
Yes.
Thaw the spinach completely and squeeze out as much excess moisture as possible.
Too much water can make the casserole soggy.
Fresh spinach generally provides the best texture.
Can I Add More Vegetables?
Yes.
Good low-carb vegetable options include:
- Bell peppers
- Mushrooms
- Zucchini
- Broccoli
- Asparagus
- Kale
- Tomatoes in moderation
Cook vegetables that release a lot of moisture before adding them to the casserole.
Easy Keto Breakfast Casserole Variations
Sausage Cheddar Breakfast Casserole
Use breakfast sausage and sharp cheddar for a classic combination.
Bacon and Spinach Breakfast Casserole
Use extra bacon and spinach with mozzarella and cheddar.
Ham and Cheese Breakfast Casserole
Replace the sausage with diced cooked ham.
Mushroom and Swiss Breakfast Casserole
Add sautéed mushrooms and Swiss cheese.
Jalapeño Popper Breakfast Casserole
Add diced jalapeños, cream cheese, cheddar, and bacon.
Mexican-Style Keto Breakfast Casserole
Add cooked chorizo, diced bell peppers, cheddar, avocado, and fresh cilantro.
Broccoli Cheddar Breakfast Casserole
Add steamed broccoli and extra cheddar cheese.
Can I Use Different Cheese?
Yes.
Almost any good melting cheese can work.
Try:
- Cheddar
- Monterey Jack
- Mozzarella
- Pepper Jack
- Swiss
- Gruyère
- Colby Jack
For a stronger flavor, combine a sharp cheese with a mild melting cheese.
Can I Make This Without Heavy Cream?
Yes.
You can use whole milk, although the casserole will be slightly less rich.
For a lower-carb version, unsweetened almond milk can also be used, but the texture will be different.
How to Store Leftover Keto Breakfast Casserole
Allow the casserole to cool before covering it tightly or transferring slices to an airtight container.
Refrigerate for up to 4 days.
How to Reheat
Reheat individual slices in the microwave until warmed through.
For a larger portion, cover with foil and warm in a 325°F oven.
Avoid overheating because the eggs can become dry.
Can I Freeze Keto Breakfast Casserole?
Yes.
Allow the casserole to cool completely.
Cut it into individual portions and wrap them tightly before placing them in a freezer-safe container.
Freeze for up to 2 months.
Thaw overnight in the refrigerator before reheating.
What to Serve With Keto Breakfast Casserole
The casserole is filling on its own, but you can serve it with:
- Sliced avocado
- Fresh berries
- Green salad
- Sautéed mushrooms
- Roasted asparagus
- Fresh tomatoes
- Low-carb toast
- Fresh herbs
How Can I Make Individual Portions?
Instead of a 9×13-inch baking dish, divide the mixture between greased ramekins or a muffin pan.
Reduce the cooking time and watch carefully because smaller portions cook much faster.
Frequently Asked Questions
Is this breakfast casserole keto-friendly?
The recipe uses eggs, cheese, sausage, bacon, spinach, and other ingredients commonly used in low-carbohydrate meals. Exact carbohydrate amounts depend on the brands and ingredients you use, so check nutrition labels if you track carbohydrates precisely.
Can I use only egg whites?
Yes, but the texture will be lighter and less rich than using whole eggs.
Can I use turkey sausage?
Yes. Turkey sausage works well, although it may be leaner than traditional breakfast sausage.
Can I make this vegetarian?
Yes. Leave out the sausage and bacon and add mushrooms, spinach, broccoli, peppers, or other vegetables.
Can I make this dairy-free?
Yes. Use suitable dairy-free cream and cheese alternatives.
Why is my breakfast casserole watery?
Excess moisture usually comes from vegetables or frozen spinach. Drain vegetables thoroughly before adding them.
Why are my eggs rubbery?
Overbaking is the most common reason. Remove the casserole once the center is set and slightly springy.
Can I make this for brunch?
Absolutely. It’s an excellent make-ahead brunch recipe and can be served alongside fresh fruit, avocado, and coffee.
Recipe Card
Easy Keto Breakfast Casserole
Prep Time: 15 minutes
Cook Time: 35–40 minutes
Resting Time: 10 minutes
Total Time: About 1 hour
Servings: 8
Course: Breakfast / Brunch
Cuisine: American
Ingredients
- 10 large eggs
- 1/2 cup heavy cream
- 1 pound breakfast sausage
- 6 slices bacon
- 2 cups baby spinach
- 1/2 small yellow onion
- 1 cup shredded cheddar
- 1/2 cup Monterey Jack
- 1/4 cup Parmesan
- 1/2 teaspoon garlic powder
- 1/2 teaspoon paprika
- 1/2 teaspoon salt
- 1/4 teaspoon black pepper
- Butter or olive oil
Instructions
- Preheat oven to 375°F.
- Grease a 9×13-inch baking dish.
- Cook bacon until crisp and crumble it.
- Brown breakfast sausage in the same skillet.
- Add onion and cook until softened.
- Add spinach and cook until wilted.
- Whisk eggs, heavy cream, garlic powder, paprika, salt, and pepper.
- Stir half of the cheeses into the egg mixture.
- Spread sausage, spinach, onion, and bacon in the baking dish.
- Pour the egg mixture over the filling.
- Top with remaining cheese.
- Bake for 30–40 minutes.
- Rest for 10 minutes.
- Garnish with parsley or green onions.
- Slice and serve warm.