We hosted friends recently at our house for the weekend. Whenever we have guests, I prefer to do as much of the prep work ahead of time as possible. So it should come as no surprise that I lean on recipes like this make ahead breakfast casserole as a go-to breakfast option when entertaining people for the weekend.
Not only is this recipe super versatile, but you can assemble it entirely ahead of time and then pop it into your oven when ready to eat!
The vegetables and protein in the below Make Ahead Breakfast Casserole recipe are honestly more of a suggestion than a rule; I was using up a bunch of vegetables I had on hand, so feel free to use whatever sounds good to you as well!
Ingredients (serves 8):
- 1 (10 oz) loaf sourdough bread, cut into cubes
- 1 tablespoon olive oil
- 1 pound breakfast sausage, casings removed
- 1 medium onion, chopped
- 2 bell peppers, chopped
- 4 garlic cloves, minced
- 1 (16 oz) container sliced mushrooms
- 1 (6 oz) bag baby spinach
- salt and pepper, to taste
- 1 dozen eggs, large
- 1 cup whole milk
- 1 (8 oz) bag shredded cheddar cheese
To prepare your Make Ahead Breakfast Casserole, spray a 9×13 inch oven-safe dish (paid link) with cooking spray.
Cut your sourdough loaf into cubes.
Add enough cubed sourdough to cover the bottom of the dish.
Add a large saute pan over medium high heat. Drizzle in the olive oil and add in your sausage, breaking it up as it cooks.
When the sausage is browned and mostly cooked through, add evenly on top of your sourdough cubes, using a slotted spoon to keep as much of the olive oil in the pan as possible.
To the pan, add in your chopped onion and peppers and season with salt and pepper to taste.
Cook until the onions and peppers are fragrant. Add in your garlic cloves and cook, stirring for another 30 seconds.
Evenly spoon the onion pepper mixture onto the cubed sourdough in your dish.
Add the large saute pan back over medium high heat. Add in your mushrooms and cook until they begin to release some of their liquid.
Season with salt and pepper and add in the spinach leaves. Cook, stirring occasionally, until the spinach has wilted.
Evenly spoon the mushrooms and spinach into your dish.
While waiting for the mushrooms to cook, add the eggs, milk, and cheese to a large bowl, whisking to combine.
Pour the egg mixture evenly over the bread, sausage, and vegetable mixture in your dish.
Cover and refrigerate overnight.
When ready to cook the casserole, remove from the fridge and uncover.
Preheat your oven to 375 degrees F. Add the uncovered casserole to your oven and bake for about 45 minutes, or until the top is set and a knife inserted into the center comes out clean.
Remove from the oven and let cool for 10 minutes before serving.
This make ahead breakfast casserole is such a simple way to feed a crowd!
You could substitute bacon for the sausage or omit altogether to make a vegetarian casserole.
I strongly suggest switching the vegetables to suit your tastes, or to finish off whatever you have in your refrigerator as well!
Make Ahead Breakfast Casserole
Ingredients
- 1 10 oz loaf sourdough bread cut into cubes
- 1 tablespoon olive oil
- 1 pound breakfast sausage casings removed
- 1 medium onion chopped
- 2 bell peppers chopped
- 4 garlic cloves minced
- 1 16 oz container sliced mushrooms
- 1 6 oz bag baby spinach
- salt and pepper to taste
- 1 dozen eggs large
- 1 cup whole milk
- 1 8 oz bag shredded cheddar cheese
Instructions
- To prepare your Make Ahead Breakfast Casserole, spray a 9x13 inch oven-safe dish (paid link) with cooking spray.
- Add enough cubed sourdough to cover the bottom of the dish.
- Add a large saute pan over medium high heat. Drizzle in the olive oil and add in your sausage, breaking it up as it cooks.
- When the sausage is browned and mostly cooked through, add evenly on top of your sourdough cubes, using a slotted spoon to keep as much of the olive oil in the pan as possible.
- To the pan, add in your chopped onion and peppers and season with salt and pepper to taste. Cook until the onions and peppers are fragrant. Add in your garlic cloves and cook, stirring for another 30 seconds.
- Evenly spoon the sausage and pepper mixture onto the cubed sourdough in your dish.
- Add the large saute pan back over medium high heat. Add in your mushrooms and cook until they begin to release some of their liquid.
- Season with salt and pepper and add in the spinach leaves. Cook, stirring occasionally, until the spinach has wilted.
- Evenly spoon the mushrooms and spinach into your dish.
- While waiting for the mushrooms to cook, add the eggs, milk, and cheese to a large bowl, whisking to combine.
- Pour the egg mixture evenly over the bread, sausage, and vegetable mixture in your dish.
- Cover and refrigerate overnight.
- When ready to cook the casserole, remove from the fridge and uncover.
- Preheat your oven to 375 degrees F. Add the uncovered casserole to your oven and bake for about 45 minutes, or until the top is set and a knife inserted into the center comes out clean.
- Remove from the oven and let cool for 10 minutes before serving.
