This Easy Make-Ahead Breakfast Casserole is a hearty, crowd-pleasing dish perfect for breakfast, brunch, or even dinner. Loaded with protein, vegetables, cheese, and your choice of bread or potatoes, it’s endlessly customizable and a breeze to prepare ahead of time.

Why You’ll Love This Recipe

• Incredibly versatile with endless add-ins
• Make-ahead convenience
• Great for feeding a crowd
• Perfect for holidays, brunches, or meal prep
• Stores and reheats beautifully

ingredients

(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)

• 4 cups cubes of crusty bread (or 3 cups frozen hash brown potatoes)
• 1 teaspoon olive oil
• 1 pound ground pork sausage (casings removed)
• 1 teaspoon dried rosemary or Italian seasoning (optional)
• 3/4 cup chopped yellow onion
• 2 garlic cloves, minced
• 2 cups chopped bell peppers
• 1 cup sliced mushrooms
• 1 cup chopped fresh spinach
• 12 large eggs
• 1/4 teaspoon salt
• 1/8 teaspoon freshly ground black pepper
• 2/3 cup milk or half-and-half
• 1 cup shredded cheddar cheese
• Optional garnish: green onion and/or chopped parsley

directions

1. Grease a 9×13-inch (or 3–4-quart) baking dish. Layer bread cubes or hash browns evenly in the bottom.
2. In a large skillet, heat olive oil over medium heat. Add sausage and seasoning, cook while breaking up the meat.
3. Add onion, garlic, bell peppers, mushrooms, and spinach. Sauté until veggies are soft and sausage is cooked through.
4. Spread the sausage and vegetable mixture over the bread or potatoes.
5. In a bowl, whisk eggs, salt, pepper, milk, and cheese. Pour over the mixture in the baking dish.
6. Cover and refrigerate for at least 30 minutes, or up to 24 hours.
7. When ready to bake, let it sit at room temperature for 10–15 minutes. Preheat oven to 375°F (191°C).
8. Bake uncovered for 40–45 minutes until golden and set.
9. Let cool for 10 minutes before slicing and serving.

Servings and timing

• Servings: 12
• Prep time: 20 minutes
• Cook time: 45 minutes
• Total time: 1 hour 30 minutes

Variations

• Vegetarian: Omit sausage and add another cup of vegetables
• Different proteins: Use ground turkey, bacon, ham, or chorizo
• Alternative starch: Replace bread with cooked diced potatoes or biscuits
• Different cheeses: Try Swiss, gouda, feta, or pepper jack
• Spicy version: Add jalapeños or a sprinkle of chili flakes

storage/reheating

• Fridge: Store leftovers in an airtight container for up to 5 days
• Freezer (unbaked): Assemble, cover, and freeze for up to 3 months. Thaw in fridge overnight before baking
• Freezer (baked): Cool completely, wrap tightly, and freeze for up to 3 months. Reheat at 350°F for 25–30 minutes
• Microwave: Reheat individual portions until warmed through

FAQs

Can I use frozen hash browns instead of bread?

Yes, use 3 cups of frozen hash browns (no need to thaw) instead of bread.

Can I make this dish ahead of time?

Yes, you can prepare it up to 24 hours in advance and refrigerate before baking.

Can I freeze it?

Yes, you can freeze it baked or unbaked for up to 3 months.

Can I use pre-cooked meats?

Absolutely. Just chop and mix them into the sautéed vegetables before layering.

Do I have to cook the vegetables first?

Yes, sautéing helps reduce moisture and enhances flavor.

What type of bread is best?

Crusty or stale bread like sourdough, ciabatta, or baguette works best.

Can I make it dairy-free?

Use plant-based milk and dairy-free cheese alternatives.

How do I know it’s fully baked?

Insert a toothpick in the center—it should come out clean.

Can I halve the recipe?

Yes, halve all ingredients and bake in a 9×9-inch dish for 32–36 minutes.

What can I serve with it?

Fresh fruit, muffins, cinnamon rolls, or coffee cake make great sides.

Conclusion

This Easy Make-Ahead Breakfast Casserole is the ultimate crowd-pleaser. With endless customization options and effortless preparation, it’s perfect for holidays, brunches, or busy mornings. Enjoy it fresh from the oven or reheated—either way, it’s sure to be a favorite!

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