This Mexican Breakfast Casserole is warm, hearty, and full of bold flavor without being fussy. It’s one of those cozy breakfasts that feels special but is still easy enough for a slow morning at home. Everything bakes together in one dish, and the leftovers are just as good the next day.
Servings: 6
Total Time: 15 minutes prep + 40 minutes bake = 55 minutes
Why I Love This Recipe
The first time I made this, I wanted something comforting but more exciting than basic eggs and cheese. I used real Mexican-style spices, added beans and sausage, and when it came out of the oven, I knew it was a keeper. It smelled amazing, sliced beautifully, and tasted even better the next morning.
- It actually tastes bold and seasoned, not bland
- One baking dish means easy cleanup
- Every bite has eggs, sausage, beans, and cheese
- It reheats like a dream for busy mornings
What You’ll Need
- 1 pound breakfast sausage
- 8 large eggs
- 1 cup whole milk
- 1 cup shredded cheddar cheese
- 1/2 cup shredded Monterey Jack cheese
- 1 red bell pepper, diced
- 1 green bell pepper, diced
- 1/2 cup diced onion
- 1/2 cup black beans, drained and rinsed
- 1/2 cup corn kernels
- 1/2 cup salsa
- 1 teaspoon taco seasoning
- 1/2 teaspoon ground cumin
- 1/2 teaspoon chili powder
- 1 teaspoon salt
- 1/2 teaspoon black pepper
- 1 tablespoon olive oil
- Cooking spray
Tools You’ll Need
- Large skillet
- Mixing bowl
- Whisk
- 9×13-inch baking dish
- Measuring cups and spoons
- Spatula
Why This Recipe Works (Quick Science)
Eggs cook gently in the oven and trap moisture from the salsa, vegetables, and beans, which keeps the casserole soft and fluffy. Fat from the sausage and cheese protects the eggs from drying out. As the casserole bakes, the spices warm and bloom, spreading flavor through every bite.
Substitutions and Variations
- Swap breakfast sausage for chorizo for deeper flavor
- Use pepper jack cheese for extra heat
- Add diced jalapeños for spice
- Use dairy-free milk and cheese if needed
- Add a layer of corn tortillas for a heartier texture
Make Ahead Tips
Cook the sausage and chop the vegetables the night before and store them in the fridge. You can also fully assemble the casserole, cover it tightly, and refrigerate overnight. Bake fresh in the morning.
Cooking Instructions
Step 1: Cook the Sausage
Heat 1 tablespoon olive oil in a large skillet over medium heat. Add 1 pound breakfast sausage and break it into small crumbles. Cook until fully browned and no pink remains, then drain excess grease.
Step 2: Add Vegetables and Spices
Add 1/2 cup diced onion, diced red bell pepper, diced green bell pepper, 1 teaspoon taco seasoning, 1/2 teaspoon ground cumin, and 1/2 teaspoon chili powder. Stir and cook for 3–4 minutes until softened and fragrant.
Step 3: Add Beans and Corn
Stir in 1/2 cup black beans and 1/2 cup corn kernels. Cook for 1–2 minutes until warmed through.
Step 4: Whisk the Eggs
In a large bowl, whisk together 8 large eggs, 1 cup whole milk, 1 teaspoon salt, 1/2 teaspoon black pepper, and 1/2 cup salsa until smooth and well combined.
Step 5: Assemble the Casserole
Spray a 9×13-inch baking dish with cooking spray. Spread the sausage mixture evenly in the dish. Pour the egg mixture over the top, then sprinkle 1 cup shredded cheddar cheese and 1/2 cup shredded Monterey Jack cheese evenly.
Step 6: Bake
Bake at 375°F (190°C) for 35–40 minutes until the center is set and the top is lightly golden.
Step 7: Rest and Serve
Let the casserole rest for 5–10 minutes before slicing and serving so it holds together cleanly.
Pro Tips
- Let the casserole rest before cutting so slices stay neat
- Freshly shredded cheese melts smoother than pre-shredded
- Don’t overbake or the eggs will dry out
- Spread the fillings evenly for balanced flavor in every bite
Leftovers and Storage
Store leftovers in an airtight container in the refrigerator for up to 4 days. Reheat gently in the microwave or oven until warmed through.
Common Mistakes
- Skipping the spices, which makes the casserole bland
- Not draining sausage grease
- Overbaking the eggs
- Cutting into the casserole too soon
What to Serve With
- Fresh fruit
- Avocado slices or guacamole
- Warm tortillas
- Extra salsa or pico de gallo
FAQ
Can I freeze this casserole?
Yes. Cool completely, wrap tightly, and freeze for up to 2 months.
Can I make it spicier?
Yes, use hot salsa or add diced jalapeños.
Can I use egg whites only?
Yes, but the casserole will be lighter and less rich.
Macros Information (Approximate per Serving)
- Calories: 450
- Protein: 27g
- Fat: 33g
- Carbohydrates: 14g
Final Thoughts
This Mexican Breakfast Casserole really earns its name. It’s bold, comforting, and full of flavor while still being easy and practical. Bake it once, and it’s likely to become part of your regular breakfast rotation. If you try it, leave a comment and share how it turned out or any twists you made.