This Easy Breakfast Casserole is made with eggs, ground sausage, shredded cheese, and day-old bread. Comforting and so flavorful, it’s the perfect make-ahead breakfast or holiday brunch.
Super Easy Breakfast Casserole Recipe
Mornings welcomed with this best-ever breakfast casserole are guaranteed to be great. Hearty and delicious, but so easy to make, this amazing casserole is made with just seven main ingredients – yellow onion, ground sausage, eggs, milk, parmesan cheese, gouda cheese, and bread. The whole family will love this yummy recipe, it’s perfect for the holiday season or as a special weekend breakfast or brunch. Simply prepare ahead of time and bake the morning of – so easy!
Do I need to chill this breakfast casserole before baking it?
No. However, it is recommended. Chilling for at least 1 hour (up to overnight) in the refrigerator allows the milk and egg mixture to soak into the day-old bread making it nice and soggy perfect for baking. If you imagine French toast, the best recipes really allow the milk and eggs to soak into the slices of bread before cooking.
How to Make Breakfast Casserole
Start by spraying a large 9 x 13-inch casserole dish with non-stick cooking spray. If you plan to cook this breakfast casserole right away, preheat your oven to 350 degrees Fahrenheit, otherwise you can skip this step.
The first step is to sauté the onions and sausage in a little olive oil until fully cooked. Once cooked remove from heat and allow them to cool slightly. Next, whisk together the eggs, milk, salt, black pepper, and garlic powder until fully combined. Once the sausage has cooled a little, add the sausage and the shredded cheese to the egg mixture. If you add hot sausage to uncooked eggs, it will start to cook the eggs.
Arrange the day-old bread in the bottom of your prepared baking dish then pour the egg and meat mixture over the top.
Cover with foil and refrigerate for up to 12 hours.
Bake in a preheated 350-degree Fahrenheit oven for 35 minutes (covered) followed by an additional 25 minutes (uncovered). You know your breakfast casserole is fully cooked when the outside edges are firm and golden, and the center isn’t jiggly anymore.
Slow Cooker Breakfast Casserole
It’s easy to make this breakfast casserole in the crock pot. Simply prepare the night before, set your slow cooker to low, and let it cook as you sleep.
- Spray the bowl of your slow cooker with non-stick olive oil or butter cooking spray.
- Cook the onion and sausage in a large skillet over medium heat until cooked through. Transfer to the slow cooker with the day-old bread cubes.
- Whisk together the eggs, milk, cheese, salt, black pepper, and garlic powder until fully combined, and pour over the sausage and bread. Mix to combine everything together.
- Cook for a total of 7-8 hours, or until eggs are fully cooked. Do not cook on high heat.
Modifications and Substitutions
- Sneak in some greens by adding baby spinach or kale. You can even add sliced mushrooms, bell peppers, or tomatoes. I like to sauté the veggies before mixing them with the egg and milk mixture.
- Swap the sausage for diced ham or bacon.
- Use whatever cheese is your favorite – cheddar cheese, goat cheese, feta cheese, mozzarella cheese, Swiss, pepper Jack, Colby Jack cheese, etc.
- For a creamier, more luscious casserole, swap the whole milk for half-and-half. Or try some combination of milk plus heavy cream.
- The best type of bread will vary from family to family. I don’t usually like making breakfast casseroles with any kind of wheat bread or whole grain bread. My favorite includes day-old French bread, sourdough bread, challah bread, or Brioche.
What to Serve with Breakfast Casserole
This sausage breakfast casserole is fantastic with a side of fruit or a fresh fruit salad. I always love to serve mine with a big glass of orange juice. When I make this recipe for Christmas morning I’ll add freshly baked cinnamon rolls or blueberry muffins and tater tots.
When serving as leftovers, sometimes I’ll serve it over a pile of fresh greens, or wrap it in a warm tortilla for an easy on-the-go breakfast.
More Breakfast Recipes,
- Freezer-Friendly Croissant Breakfast Sandwichs
- Crustless Quiche
- The Best Sausage Gravy Recipe with Biscuits
- Quiche Lorraine
- Crispy Hash Browns
- Acai Bowl Recipe
- Pumpkin French Toast Casserole
If you try making this Breakfast Casserole Recipe, please leave me a comment below! I always love to read your thoughts and feedback!
- 1 tablespoon olive oil
- 1 yellow onion - diced
- 1 pound ground sausage - see notes
- 8 large eggs
- 3 cups whole milk - see notes
- ½ teaspoon salt
- 1 teaspoon black pepper
- 1 teaspoon garlic powder
- 1 cup parmesan cheese - grated
- 1 cup gouda cheese - shredded
- 10 cups day-old-bread - cut into large cubes
- fresh parsley - to garnish
- Preheat oven to 350 degrees Fahrenheit and spray a large 9 x 13-inch baking dish with non-stick cooking spray. Set aside.
- Meanwhile, heat the olive oil in a large skillet over medium heat. Add the onion and cook for 2-3 minutes, or until the onion turns translucent. Add the ground sausage and cook until the sausage is fully cooked. Remove from heat and set aside.
- In a medium bowl whisk together the eggs, milk, salt, black pepper, and garlic powder until fully combined.
- Once the sausage has cooled, add the shredded cheese and cooked sausage to the egg mixture. Mix well.
- In the bottom of your prepared 9 x 13-inch baking dish arrange the diced day-old bread in an even layer. Pour the egg and meat mixture over the top.
- Cover the baking dish with aluminum foil and refrigerate for up to 12 hours (optional, but recommended).
- When ready to bake, tent with foil and bake for 35 minutes, then remove the foil and bake for an additional 25 minutes or until the outside edges are firm and golden and the center isn't jiggly anymore.
- Remove from the oven and allow to cool for 5 minutes before serving.
- Leftovers: Store in an airtight container in the refrigerator for up to 5 days.
- To Freeze: Once the casserole is prepared, but before baking, cover it with plastic wrap and aluminum foil and freeze for up to 3 months.
- To Thaw: Thaw overnight in the refrigerator before baking.
- Total baking time will vary. You know your casserole is ready when the edges are golden brown and the center is no longer jiggly.
- This recipe can be made with hot or sweet Italian sausage or your favorite breakfast sausage. If preferred, swap the sausage for diced ham.
- This recipe is best when it’s made with whole milk or a combination of milk (2% or whole milk) with heavy cream. It just depends on how heavy and rich you like your breakfast casseroles to be.
(Nutrition information provided is an estimate and will vary based on cooking methods and specific brands of ingredients used.)