I love a plate of scrambled eggs or a stack of fluffy buttermilk pancakes, but anytime I’m hosting a weekend breakfast or holiday brunch and need to feed a crowd, the last thing I want is to be stuck in the kitchen standing over the stove. For these occasions, I always serve up a warm and comforting loaded breakfast casserole. In this classic version, there’s a little something for everyone, from crumbled breakfast sausage to a mix of tender veggies to fluffy eggs. And best of all, it can be prepped the night before — so come morning, all you have to do is slide it into the oven.

Why you’ll love it

Key ingredients

Helpful swaps

What to Serve with a breakfast casserole

Breakfast Casserole

Serves 8 to 10

Cooking spray

1 tablespoon olive oil

1 pound uncooked breakfast sausage, casings removed if needed

1 medium yellow onion, diced (about 1 1/2 cups)

1 medium red bell pepper, diced (about 1 1/2 cups)

1 1/2 teaspoons kosher salt, divided

3 ounces baby spinach (about 3 packed cups)

12 large eggs

2 cups half-and-half

1 tablespoon Dijon mustard

1/2 teaspoon freshly ground black pepper

1 (20-ounce) bag frozen shredded hash brown potatoes (do not thaw, about 6 1/2 cups)

6 ounces sharp cheddar cheese, shredded (about 1 1/2 cups), divided

1. Heat the oven to 375 F. Lightly coat a 9-by-13-inch baking dish with cooking spray or oil.

2. Heat 1 tablespoon olive oil in a large skillet over medium heat until shimmering. Add 1 pound uncooked pork breakfast sausage and cook, breaking it up into small pieces with a wooden spoon, until no longer pink, 6 to 8 minutes.

3. Stir in 1 diced medium yellow onion, 1 diced medium red bell pepper, and 1/2 teaspoon of the kosher salt. Cook, stirring occasionally, until the onion is softened, 3 to 5 minutes. Stir in 3 ounces baby spinach. Cook until wilted, about 1 minute. Transfer to the baking dish.

4. Whisk 12 large eggs, 2 cups half-and-half, 1 tablespoon Dijon mustard, the remaining 1 teaspoon kosher salt, and 1/2 teaspoon black pepper in a large bowl until combined.

5. Add 20 ounces frozen shredded potatoes (if it’s frozen into big clumps, smash the unopened bag against a hard surface to break them up first) and half of the shredded sharp cheddar cheese (about 3/4 cup) to the baking dish. Stir until combined and spread into an even layer.

6. Pour the egg mixture over the potato mixture. Tilt the baking dish so the egg mixture is in an even layer if needed. Sprinkle with the remaining 3/4 cup cheddar.

7. Bake until a knife inserted in the middle comes out clean and the top is light golden-brown, 55 to 60 minutes. Let cool for 5 minutes before serving.

Make ahead notes

Storage notes

(Kelli Foster is a culinary producer for TheKitchn.com, a nationally known blog for people who love food and home cooking. Submit any comments or questions to editorial@thekitchn.com.)

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