Ever struggled to find a satisfying breakfast that won’t kick you out of ketosis or leave you hungry an hour later? This Keto Sausage Breakfast Casserole is about to become your new morning MVP. It’s loaded with protein, healthy fats, and just enough vegetables to make you feel virtuous—all while containing almost zero carbs. The best part? You can make it ahead of time, which means your future self will thank you when all you have to do is reheat a slice instead of cooking while caffeine-deprived. Whether you’re strictly keto, low-carb curious, or just someone who appreciates a hearty breakfast without the carb crash, this casserole delivers.
Why This Recipe is Awesome
This isn’t just another egg casserole—it’s a flavor-packed, meal-prep friendly powerhouse that solves the eternal “what’s for breakfast” question for days at a time.
The macros are absolutely perfect for keto. High fat, moderate protein, and minimal carbs create the ideal balance to keep you in ketosis while actually satisfying your hunger. No more mid-morning snack attacks or energy crashes!
What I love most about this recipe is its incredible versatility. The basic formula stays the same, but you can easily swap proteins, vegetables, and cheeses based on what you have on hand or what you’re craving. It’s the Swiss Army knife of keto breakfasts.
Plus, this casserole works for any meal of the day. Sure, it’s called a breakfast casserole, but it’s equally delicious for lunch, dinner, or even a midnight snack. Breakfast foods know no time constraints, especially when they’re this good.
Keto Sausage Breakfast Casserole
Ingredients
- 1 pound breakfast sausage check label for no added sugar to keep it keto
- 8 large eggs
- 1/2 cup heavy cream
- 2 cups shredded cheese divided (cheddar, Monterey Jack, or a blend)
- 1 small bell pepper diced (any color)
- 1/2 medium onion finely diced
- 2 cups fresh spinach roughly chopped
- 2 cloves garlic minced
- 1 teaspoon dried herbs oregano, Italian seasoning, or herbs de Provence
- 1/2 teaspoon salt
- 1/4 teaspoon black pepper
- 1/4 teaspoon red pepper flakes optional
- 1 tablespoon butter or oil for greasing the dish
Instructions
- Preheat your oven to 375°F (190°C). Grease a 9×13 inch baking dish with butter or oil and set aside.
- Cook the sausage. In a large skillet over medium heat, brown the breakfast sausage, breaking it up into crumbles as it cooks, about 5-7 minutes. If the sausage is lean, you may need to add a little oil to the pan first.
- Sauté the vegetables. Once the sausage is mostly cooked through, add the diced onion and bell pepper to the skillet. Cook for an additional 3-4 minutes until the vegetables are softened. Add the garlic and cook for another 30 seconds until fragrant.
- Add the spinach. Stir in the chopped spinach and cook just until wilted, about 1-2 minutes. Remove the skillet from heat and let the mixture cool slightly.
- Whisk the eggs. In a large bowl, whisk together the eggs, heavy cream, dried herbs, salt, black pepper, and red pepper flakes (if using) until well combined.
- Combine and assemble. Spread the slightly cooled sausage and vegetable mixture evenly in the prepared baking dish. Sprinkle 1 cup of the shredded cheese over the sausage mixture. Pour the egg mixture over the top, ensuring it's evenly distributed. Top with the remaining 1 cup of shredded cheese.
- Bake to perfection. Place the baking dish in the preheated oven and bake for 35-40 minutes, or until the center is set and the top is golden brown. The casserole should be slightly puffed up and a knife inserted in the center should come out clean.
- Rest before serving. Allow the casserole to rest for about 5 minutes before slicing. This helps it set up for cleaner slices.
- Slice and enjoy. Cut into 8 squares and serve hot. Garnish with sliced green onions or a dollop of sour cream if desired.
Notes
- Make-ahead magic: This casserole can be fully assembled the night before and refrigerated, covered, overnight. Just add 5-10 minutes to the baking time if cooking straight from the refrigerator.
- Batch cooking: Once baked and cooled, individual portions can be wrapped and refrigerated for up to 5 days or frozen for up to 3 months. Reheat in the microwave for 60-90 seconds.
- Watch the moisture content. Some vegetables release a lot of water. If using water-heavy vegetables like zucchini or mushrooms, consider cooking them separately until their moisture has evaporated before adding to the casserole.
- Check your sausage labels carefully. Many commercial sausages contain added sugars and fillers. Look for brands that list just meat and spices in the ingredients for truly keto-friendly options.
- For a spicier version, use hot Italian sausage or add a diced jalapeño with the bell pepper.
- Cheese selection: While cheddar is classic, don’t be afraid to experiment with other varieties like Gruyère, goat cheese, or pepper jack for different flavor profiles.
- If your casserole starts browning too quickly on top, cover it loosely with aluminum foil for the remainder of the baking time.
Calories & Nutritional Info
- Calories: Approximately 350-380 per serving
- Protein: 22g
- Fat: 28g
- Net Carbs: 3g
- Fiber: 1g
- Total Carbs: 4g
- Sodium: 650mg (varies based on sausage brand)
- Calcium: 20% of daily value
- Vitamin A: 15% of daily value
- Vitamin C: 20% of daily value (from bell peppers)
- Iron: 10% of daily value
Common Mistakes to Avoid
- Using pre-shredded cheese. These often contain anti-caking agents with added carbs. Grate your own for better melting and fewer additives.
- Not fully cooking the vegetables. Any vegetables added should be pre-cooked to remove excess moisture, or your casserole may end up watery.
- Skipping the resting period. Cutting into the casserole immediately after baking can result in a runny texture. Those 5 minutes of patience make a big difference!
- Overcooking the eggs. Bake just until set for the best texture. Overcooked eggs become rubbery and less appetizing.
- Using low-fat dairy. This is a keto recipe, so embrace the full-fat versions of cream and cheese. They provide better flavor, texture, and keep you fuller longer.
- Not seasoning adequately. Eggs need proper seasoning or they can taste bland. Don’t be shy with salt, pepper, and herbs.
- Forgetting to grease the baking dish. This simple step prevents sticking and makes clean-up much easier.
Alternatives & Substitutions
- Protein options: Swap the breakfast sausage for ground beef, ground turkey, diced ham, bacon, or even shredded rotisserie chicken.
- Vegetable variations: Use keto-friendly vegetables like mushrooms, zucchini, broccoli, cauliflower, or kale instead of or in addition to the bell peppers and spinach.
- Cheese alternatives: Almost any cheese works well—try Swiss, feta, mozzarella, or a Mexican blend for different flavor profiles.
- Heavy cream substitutes: Unsweetened almond milk or coconut milk can work, though the casserole won’t be quite as rich. You can add an extra egg to help with setting.
- Herbs and seasonings: Try different spice blends like Cajun seasoning, taco seasoning, or fresh herbs like dill or chives.
- Add healthy fats: Mix in diced avocado just before serving, or top with sliced avocado for extra creaminess and healthy fats.
- Dairy-free version: Use coconut cream instead of heavy cream and omit the cheese or use a dairy-free cheese alternative.
- Spice it up: Add a can of diced green chiles or a diced jalapeño for a Southwestern kick.
FAQs
Can I make this casserole in advance?
Absolutely! It’s perfect for meal prep. You can prepare it entirely the night before and refrigerate, then bake in the morning. Alternatively, bake it ahead of time, slice into portions, and refrigerate or freeze for quick grab-and-go breakfasts throughout the week.
How do I know when the casserole is fully cooked?
The casserole is done when the center is set and doesn’t jiggle when you gently shake the pan. A knife inserted in the center should come out clean, and the top should be lightly golden. The internal temperature should reach 160°F.
Can I freeze this casserole?
Yes! You can freeze it either before or after baking:
- Unbaked: Assemble, cover tightly, and freeze for up to 2 months. Thaw overnight in the refrigerator before baking.
- Baked: Cool completely, slice into portions, wrap individually, and freeze for up to 3 months. Reheat individual slices in the microwave for 1-2 minutes.
What if I don’t eat pork?
No problem! You can use turkey breakfast sausage, ground chicken, or beef instead. For a vegetarian version, increase the vegetables and add some chopped nuts for texture and protein.
Is this casserole good for meal prep?
It’s PERFECT for meal prep. It reheats beautifully and actually tastes even better the next day as the flavors meld together. Many keto followers make this on Sunday for ready-made breakfasts all week long.
How long will leftovers keep in the refrigerator?
Store leftovers in an airtight container in the refrigerator for up to 5 days. Make sure the casserole has cooled completely before storing to prevent condensation, which can make it soggy.
Can I make this in a smaller batch?
Yes! You can easily halve this recipe and bake it in an 8×8 inch dish. The baking time will be slightly shorter, so start checking for doneness around the 25-30 minute mark.
Final Thoughts
This Keto Sausage Breakfast Casserole is more than just a meal—it’s a strategy for success on a ketogenic diet. By preparing this protein and fat-rich dish ahead of time, you eliminate the morning decision fatigue that can lead to poor food choices, while ensuring you start your day with a satisfying meal that keeps your energy steady and cravings at bay.
What makes this recipe particularly valuable is its adaptability. The basic formula provides a framework that you can customize based on your preferences, what’s in season, or simply what needs to be used up in your refrigerator. It’s a practical approach to keto eating that acknowledges real life doesn’t always align with perfect meal plans.
Whether you’re a longtime keto devotee, just starting out on your low-carb journey, or simply looking for a protein-packed breakfast option that won’t leave you hungry an hour later, this casserole deserves a place in your recipe repertoire. It proves that keto eating doesn’t have to be complicated, monotonous, or time-consuming—it can be as simple as a slice of delicious casserole waiting for you in the refrigerator.
