Classic Make-Ahead Sausage and Hashbrown Breakfast Casserole
A hearty, crowd-pleasing breakfast casserole layered with crispy hashbrowns, savory breakfast sausage, fluffy eggs, and sharp cheddar cheese. Perfect for assembling the night before and baking fresh in the morning.
Equipment
- 9x13-inch baking dish
- large skillet
- large mixing bowl
- whisk
- spatula
- aluminum foil
Ingredients
Meat and Vegetables
- 1 pound ground breakfast sausage — mild or hot, depending on preference
- 0.5 cup yellow onion — finely diced
- 0.5 cup red bell pepper (optional) — finely diced
Base and Dairy
- 20 ounces frozen shredded hashbrowns — thawed slightly
- 2 cups sharp cheddar cheese — freshly grated, divided
- 8 whole large eggs
- 2 cups whole milk — can substitute with half-and-half for a richer casserole
Seasonings
- 1 teaspoon salt
- 0.5 teaspoon black pepper — freshly cracked
- 1 teaspoon dry mustard powder
- 0.5 teaspoon garlic powder
Meat and Vegetables
| 1 pound | ground breakfast sausage | mild or hot, depending on preference |
| 0.5 cup | yellow onion | finely diced |
| 0.5 cup | red bell pepper (opt.) | finely diced |
Base and Dairy
| 20 ounces | frozen shredded hashbrowns | thawed slightly |
| 2 cups | sharp cheddar cheese | freshly grated, divided |
| 8 whole | large eggs | |
| 2 cups | whole milk | can substitute with half-and-half for a richer casserole |
Seasonings
| 1 teaspoon | salt | |
| 0.5 teaspoon | black pepper | freshly cracked |
| 1 teaspoon | dry mustard powder | |
| 0.5 teaspoon | garlic powder |
Instructions
-
Grease a 9x13-inch baking dish with non-stick cooking spray or butter.
~2 min -
In a large skillet over medium-high heat, cook the breakfast sausage, breaking it apart with a spatula. Once it starts to brown, add the diced onion and bell pepper. Cook until the sausage is fully browned and the vegetables are tender, about 5-7 minutes. Drain excess grease and set aside to cool slightly.
~8 minDraining the grease prevents the casserole from becoming oily. -
Spread the thawed hashbrowns evenly along the bottom of the prepared baking dish.
~2 minYou don't need to cook the hashbrowns first; they will cook perfectly in the casserole. -
Top the hashbrown layer evenly with the cooked sausage and vegetable mixture, followed by 1.5 cups of the shredded cheddar cheese.
~2 minReserve the remaining 0.5 cup of cheese for the top of the casserole. -
In a large mixing bowl, whisk together the eggs, milk, salt, black pepper, dry mustard powder, and garlic powder until well combined and frothy.
~4 minThe dry mustard powder adds a wonderful depth of flavor that complements the eggs and cheese. -
Carefully pour the egg mixture evenly over the hashbrown, sausage, and cheese layers in the baking dish. Sprinkle the remaining 0.5 cup of cheese over the top.
~2 min -
Cover the baking dish tightly with aluminum foil or a fitted lid and place it in the refrigerator overnight (or for at least 2 hours to allow the flavors to meld).
~8hIf you are in a rush, you can bake this immediately, but letting it sit overnight yields the best texture. -
The next morning, preheat your oven to 375°F (190°C). Take the casserole out of the refrigerator and let it sit at room temperature while the oven preheats.
~15 minTaking the chill off the dish ensures even baking. -
Bake the casserole covered with foil for 30 minutes. Then, remove the foil and bake for an additional 20-25 minutes, or until the edges are golden brown and the center is completely set.
~55 minTo check for doneness, insert a knife into the center; it should come out clean. -
Remove from the oven and let the casserole rest for 5-10 minutes before slicing and serving.
~10 minResting helps the casserole firm up, making it easier to cut into clean squares.
Tips & Storage
- Grate your own cheese from a block rather than using pre-shredded bagged cheese; it melts much better and lacks the powdery coating.
- For a spicy kick, use hot breakfast sausage and add a few dashes of hot sauce to the egg mixture.
- If your hashbrowns are completely frozen solid, microwave them for 1-2 minutes just to break them apart before layering.
- Storage: Store leftover casserole in an airtight container in the refrigerator for up to 4 days. Reheat individual slices in the microwave for 1-2 minutes, or cover with foil and reheat in a 350°F oven until warmed through. You can also freeze baked, cooled portions for up to 2 months.