Easy Breakfast Casserole – 45-Minute One-Pan Meal

Breakfast casserole is my go-to when I need to feed a crowd without standing over the stove. It's hearty, cheesy, and endlessly customizable—plus it comes together in one dish.

I started making this for holiday mornings when the family was visiting. Now it's requested for birthdays, brunches, and even lazy Sundays. It's the kind of dish that makes everyone feel at home.

The best part? You can prep it the night before, pop it in the oven in the morning, and enjoy a hot, satisfying breakfast with zero fuss.

About the Ingredients

8 large eggs

The base of the casserole. For a lighter option, use 6 eggs and 1 cup of liquid egg whites.

1 cup (240ml) milk

Adds creaminess. Any milk works; for richer flavor, use half-and-half.

1 lb (450g) breakfast sausage

Provides savory, seasoned protein. Substitute with cooked bacon, ham, or turkey sausage.

3 cups (about 240g) frozen shredded hash browns, thawed

Adds texture and bulk. Use cubed potatoes if preferred; squeeze out excess moisture.

1 cup (120g) shredded cheddar cheese

Melty and sharp. Try pepper jack for heat or Swiss for nuttiness.

1/2 cup (50g) shredded mozzarella cheese

Adds gooeyness. Use any melting cheese like Monterey Jack.

1/2 cup (75g) diced bell pepper (any color)

Adds color and crunch. Use frozen peppers if fresh isn't available.

1/4 cup (40g) diced onion

Adds savory depth. Use shallots or leeks for a milder flavor.

1 teaspoon salt

Enhances all the flavors. Adjust based on the saltiness of your sausage.

1/2 teaspoon black pepper

Adds a subtle kick. Use freshly ground for best flavor.

1/2 teaspoon garlic powder

Adds aromatic depth. Use fresh minced garlic if you prefer.

Tips & Tricks

• Thaw the hash browns and pat them dry with a paper towel to prevent a watery casserole.
• If you're prepping ahead, assemble everything but the topping cheese, cover, and refrigerate. Add the cheese right before baking.
• Don't overbake! The casserole should be just set in the center; it will continue to cook as it rests.

Step-by-Step Instructions

1. Preheat and prep

Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking dish with butter or nonstick spray.

2. Brown the sausage

In a skillet over medium-high heat, cook the sausage, breaking it into crumbles, until browned and cooked through, about 5-7 minutes. Drain excess fat if needed.

3. Mix the egg base

In a large bowl, whisk together the eggs, milk, salt, pepper, and garlic powder until fully combined and slightly frothy.

4. Layer the casserole

Spread the thawed hash browns evenly in the prepared dish. Sprinkle the cooked sausage, bell pepper, and onion over the top.

5. Pour and top

Pour the egg mixture over the hash browns and sausage. Sprinkle both cheeses evenly over the top.

6. Bake until set

Bake for 35-40 minutes, until the edges are golden brown and the center is set (a knife inserted in the middle comes out clean). The internal temperature should reach 165°F (74°C).

7. Rest and serve

Let the casserole rest for 5-10 minutes before slicing. This helps it hold its shape. Serve warm.

Delicious Variations

Vegetarian

Skip the sausage and add 1 cup of diced mushrooms and 1 cup of spinach.

Southwest

Add 1 can of drained black beans and 1/2 cup of salsa; use pepper jack cheese.

Ham and Swiss

Substitute ham for sausage and Swiss cheese for cheddar; add a pinch of nutmeg.

How to Store Breakfast Casserole

Frequently Asked Questions

I hope this breakfast casserole becomes a staple in your home like it is in mine. Give it a try, and don't be afraid to make it your own. Happy cooking! Small steps, big impact.

Breakfast Casserole

Breakfast Casserole: a hearty, make-ahead egg bake loaded with sausage, cheese, and veggies. Perfect for busy mornings and holiday brunches.

★★★★½ 4.8 (127 ratings)

15 minPrep time35 minCook time6Servings285 kcalCalories

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🧂 Ingredients

• 8 large eggs
• 1 cup (240ml) milk
• 1 lb (450g) breakfast sausage
• 3 cups (about 240g) frozen shredded hash browns, thawed
• 1 cup (120g) shredded cheddar cheese
• 1/2 cup (50g) shredded mozzarella cheese
• 1/2 cup (75g) diced bell pepper (any color)
• 1/4 cup (40g) diced onion
• 1 teaspoon salt
• 1/2 teaspoon black pepper
• 1/2 teaspoon garlic powder

📋 Instructions

1. 1Preheat and prep — Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking dish with butter or nonstick spray.
2. 2Brown the sausage — In a skillet over medium-high heat, cook the sausage, breaking it into crumbles, until browned and cooked through, about 5-7 minutes. Drain excess fat if needed.
3. 3Mix the egg base — In a large bowl, whisk together the eggs, milk, salt, pepper, and garlic powder until fully combined and slightly frothy.
4. 4Layer the casserole — Spread the thawed hash browns evenly in the prepared dish. Sprinkle the cooked sausage, bell pepper, and onion over the top.
5. 5Pour and top — Pour the egg mixture over the hash browns and sausage. Sprinkle both cheeses evenly over the top.
6. 6Bake until set — Bake for 35-40 minutes, until the edges are golden brown and the center is set (a knife inserted in the middle comes out clean). The internal temperature should reach 165°F (74°C).
7. 7Rest and serve — Let the casserole rest for 5-10 minutes before slicing. This helps it hold its shape. Serve warm.

👨‍🍳 Chef's Note: If you prefer a crustless quiche-like texture, simply skip the hash browns and add an extra 1/2 cup of milk.

Servings: 6

Cuisine: American

Course: Breakfast

Nutrition (per serving): 285 kcal · 12g protein · 22g carbs · 9g fat

Written by Maya Chen

Maya writes about sustainable living and zero-waste practices, focusing on small, actionable changes for everyday life. She shares practical tips from her own experiments in reducing plastic and food waste.