Breakfast Casserole
This satisfying dish boasts a scrumptious marriage of fluffy eggs, savory sausage, sharp cheese, and aromatic vegetables. The iconic breakfast casserole has been a fan favorite since the mid 20th century, when oven-safe cookware became available, and when one-pot meals became an economical and time-saving way to feed family and friends.
This recipe was written for the Arizona Republic.
This classic breakfast casserole features easy-to-find ingredients (I practically named all of them), and it’s exceptionally easy to assemble. And since the dish is prep-ahead friendly, it’s ideal for busy weekends, community potlucks, hungry houseguests, and holiday gatherings.
Ingredients for breakfast casserole
- Sausage. This recipe calls for two pounds of sausage, and you have a variety of options. I used mild pork sausage, but you can also use mild Italian or hot Italian sausage. Breakfast sausage is also an option, just make sure to remove the casings before cooking. For a pork-free casserole, swap in your favorite variety of chicken or plant-based sausage.
- Eggs. You will need one dozen large eggs for this recipe. Choose your desired brand and grade level; every option will work here.
- Sour cream and milk. Milk and tangy sour cream are used to add moisture and richness to the casserole. The sour cream also adds a slight tang that partners well with the sweet vegetables. I prefer full-fat varieties of both products, but feel free to use reduced-fat versions, such as light sour cream and 2% milk. I do not recommend fat-free products or skim milk because they tend to curdle when heated.
- Green onions. Fresh, grassy green onions (scallions) add bright color and a sweeter, mild onion flavor. If desired, you may swap in chopped red onion (about ¼ cup).
- Bell peppers. Sweet bell peppers add great color and flavor to this recipe. In fact, their sweetness is enhanced when sautéed and then baked in the casserole. I used orange and yellow bell peppers for their vibrant hues, knowing they would complement the green onions and parsley. That said, you can use any color bell peppers, or one single bell pepper. I like the combination of two colors for visual appeal and presentation, but it’s not necessary.
- Parsley. Fresh parsley lends a noticeable pop of color and fresh flavor. I don’t recommend dried parsley if you can avoid it. If essential, you may substitute 2 teaspoons dried parsley for the fresh.
- Italian seasoning. A small amount of Italian seasoning adds floral depth to this casserole. Since Italian seasoning is a blend of basil, oregano, thyme, and rosemary, it’s an easy way to add tremendous flavor with one product.
- Cheese. Cheddar cheese is the classic choice for breakfast casserole because it’s sharp and robust and can hold up to the bold flavors of the sausage. If desired, you may swap in a different cheese, or a combination of cheeses. Optimal choices include Monterey jack, pepper jack, mozzarella, Italian cheese blend, Mexican cheese blend, gouda, Swiss, and parmesan.
- Salt and black pepper. The sausage provides most of the seasoning for this casserole, so we use salt and pepper to enhance the taste of all other ingredients.
Variations to consider
- Use different vegetables. I used bell peppers and green onions, but feel free to replace them with sliced mushrooms, spinach, asparagus, broccoli, peas, corn, or mixed vegetables. Any vegetables you crave or happen to have in your fridge or freezer will work. Frozen vegetables do not need to be sautéed or thawed before baking.
- Add rice. If you want to add heft to this casserole, fold 2 cups of cooked rice into the egg mixture before transferring it to the baking dish.
- Add potatoes. For a potato-rich breakfast casserole, add 2 cups of frozen and thawed hash browns to the egg mixture before transferring it to the baking dish.
- Make it extra cheesy. Top the casserole with 1 ½ cups of shredded cheese before baking. Excellent choices include cheddar, mozzarella, Mexican cheese blend, or a combination of cheeses.
How to prep this casserole in advance
You can assemble this casserole up to 24 hours before cooking. Prepare the dish as directed, up until baking. Cover the baking dish with plastic wrap and refrigerate for up to 24 hours. Pull the casserole from the refrigerator 30 minutes before baking. If the center of the casserole is still cold, you may need to add a few minutes to the cooking time.
You can also freeze this casserole before baking! Assemble as directed, up until baking. Cover with plastic wrap and aluminum foil and freeze for up to 3 months. Thaw overnight in the refrigerator. Remove the casserole from the refrigerator 30 minutes before baking. If the center of the casserole is still cold, you may need to add a few minutes to the cooking time.
How to store leftover breakfast casserole
Once cool, transfer leftover breakfast casserole to an airtight container and refrigerate for up to 3 days or freeze up to 3 months. Thaw leftovers overnight in the refrigerator. Reheat individual portions in the microwave, or in a 300-degree F oven for 15 minutes, until hot all the way through to the center.
Breakfast Casserole
Ingredients
- 12 large eggs
- 1 cup sour cream, preferably full fat
- ¼ cup milk, preferably whole or 2%
- 2 pounds ground sausage
- ½ orange or red bell pepper, seeded and diced
- ½ yellow bell pepper, seeded and diced
- 4 green onions, chopped
- ½ teaspoon Italian seasoning
- Salt and freshly ground black pepper
- 2 cups shredded cheddar cheese
- 2 tablespoons chopped fresh parsley
Instructions
- Preheat the oven to 350 degrees F. Coat a 13×9-inch baking dish with cooking spray or a thin layer of olive oil.
- In a large bowl, whisk together the eggs, sour cream, and milk. Set aside.
- Brown the sausage in a large skillet over medium-high heat, breaking up the meat as it cooks.
- Add the pork to the egg mixture, reserving about 2 teaspoons of grease in the pan.
- Add the bell peppers and green onion to the same pan (with the leftover pork grease) over medium-high heat. Cook for 3 to 5 minutes, until the vegetables soften.
- Add the Italian seasoning, ½ teaspoon salt, and ¼ teaspoon black pepper to the vegetables and cook for 1 minute, until fragrant.
- Add the vegetables to the egg mixture, along with the cheese and parsley. Stir to combine.
- Transfer the mixture to the prepared pan.
- Bake for 35 to 45 minutes, until the edges of the casserole are golden and set and the center is still barely jiggly.
- Cool the pan on a wire rack for at least 10 minutes before slicing and serving.