breakfast egg casserole

A satisfying American breakfast or brunch dish featuring eggs, sausage, and cheese, baked in a 9×13-inch dish. It can be prepared ahead of time and is easy to customize with various vegetables and meats.

Ingredients

• 10 large eggs
• 1 cup whole milk
• 1 pound breakfast sausage
• 1 cup shredded cheddar cheese
• ½ cup shredded mozzarella cheese
• ½ medium onion, finely diced
• 1 small bell pepper, diced
• 1 cup fresh spinach, chopped
• ½ teaspoon garlic powder
• ½ teaspoon salt
• ¼ teaspoon black pepper
• ½ teaspoon paprika
• 1 tablespoon butter or cooking oil
• 2 tablespoons chopped fresh parsley, optional
• ¼ cup sliced green onions, optional

Instructions

1. Preheat your oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish with butter or cooking spray. Allow eggs, milk, and cheese to come close to room temperature.
2. Heat a large skillet over medium heat. Add the breakfast sausage and cook for approximately 6–8 minutes, breaking it apart until completely browned. Drain excess grease if necessary.
3. Add the diced onion and bell pepper to the cooked sausage. Cook for another 3–4 minutes until vegetables soften. Add the chopped spinach and cook for about 1–2 minutes until wilted. Set aside.
4. Crack all 10 eggs into a large mixing bowl. Add the milk, garlic powder, salt, black pepper, and paprika. Whisk thoroughly for about 1–2 minutes until completely combined and smooth, avoiding over-whisking.
5. Spread the cooked sausage and vegetable mixture evenly across the bottom of the prepared baking dish. Sprinkle approximately half of the cheddar and mozzarella cheese over the mixture.
6. Pour the beaten egg mixture evenly over everything in the dish. Gently shake or tilt the dish to distribute the eggs. Sprinkle the remaining cheese evenly over the top. Optionally scatter sliced green onions or chopped parsley.
7. Bake uncovered for approximately 40–45 minutes. The casserole is ready when the center is set, edges are lightly golden, and cheese is melted and bubbling. If the top browns too quickly, loosely cover with aluminum foil.
8. Remove from the oven and allow to rest for 5–10 minutes before slicing. Garnish with fresh parsley or green onions if desired. Slice into eight portions and serve warm.

Notes

Make-Ahead: Assemble the casserole but do not bake. Cover tightly and refrigerate overnight. Bake the next morning at 375°F (190°C) for 45–55 minutes. Variations: For a vegetarian version, omit sausage and add mushrooms, zucchini, tomatoes, or broccoli. For a spicier version, use spicy sausage and add jalapeños. Storage: Refrigerate leftovers in airtight containers for up to 3–4 days. Can be frozen in individual portions; thaw overnight in the refrigerator before reheating.