Perfect Sausage Breakfast Casserole Recipe

Sausage breakfast casserole is the quintessential brunch treat, but it could also honestly serve as a creative breakfast-for-dinner option too. Either way, it's fun to make and a total crowd pleaser. 

We like this sausage breakfast casserole recipe from food blogger, recipe developer, and curator of Probably in the Kitchen, Erin Johnson, because it's also easily customizable depending on your preferences and what you have available in your kitchen. "This casserole is a great way to use up any veggies you have on hand! The only limit is your imagination," explains Johnson. "I like to add in mushrooms and spinach if I have them on hand. You can even change up the cheese if there is one you prefer." 

This recipe yields around eight servings, so if you're feeding more than eight people, you might want to double up and make two casseroles. Read on for more details on how to give off cute breakfast joint restaurant vibes in your own kitchen.

We like to get a sense of everything we're working with and prep anything that might need prepping before we start cooking a recipe. 

For this sausage breakfast casserole, you'll need a pound of breakfast sausage, a bag of diced hash browns with onions (refrigerated or frozen and thawed), a clove of garlic, minced, one cup of bell peppers, chopped, eight eggs, a half cup of milk, and two cups of cheddar cheese. Some optional items include green onions, different veggies, and maybe some hot sauce.

A note from Johnson regarding the potatoes: "I used refrigerated hash browns, but you can use frozen—just thaw them first. If you use the O'Brien style frozen potatoes, you can eliminate adding the onions and peppers, although I prefer to add them regardless because the fresh veggies add a nice flavor and texture."

Once you've got all of your sausage breakfast casserole ingredients ready, preheat the oven to 375 degrees Fahrenheit, then start on the items that need some pre-cooking on the stove. 

In a large skillet, brown the sausage on medium high until it is cooked through. Remove it from then skillet, drain any excess grease, and reserve.

By the way, the sky is the limit when it comes to the type of sausage you decide to use. "The variety of sausage you use is totally up to you," says Johnson. "I prefer using regular breakfast sausage, but hot will add a significant boost in flavor and spice if that is your preference."

After you've removed the sausage from the skillet for this sausage breakfast casserole, you can add the onions and peppers, then sauté until the onions are translucent. Next, put the garlic in the skillet and cook for an additional minute.

As previously mentioned, you can save yourself the hassle of chopping onions and peppers if you buy frozen hash browns that already have those items cooked in, but there is a nice freshness added by using the produce that's, well, fresh.

After you've cooked the sausage, onions, and peppers, you can start preparing the actual casserole part of this sausage breakfast casserole recipe.

Spray a 13x9-inch baking dish with cooking spray (so you don't end up with half your ingredients stuck to the bottom of the dish when it's done cooking), then layer the potatoes across the bottom of the baking dish. Season the potatoes with salt and pepper. Next, layer the cooked sausage over the potatoes, and finally, add the vegetables over the sausage. It should look very pretty and colorful when you're done.

Post-casserole layering, you're going to whisk together the eight eggs. Once the eggs are thoroughly whisked, mix in the half cup of milk and one cup of the cheese. This is your egg mixture. Pour the egg mixture over the top of the casserole.

If you are making this sausage breakfast casserole ahead of time, Johnson suggests doing this step on the day of baking and eating, not on the day you assemble the casserole. She instructs, "If you want to get a jump-start on breakfast, you can assemble this the night before—just wait until morning to mix and pour over the eggs!"

The final direction in this sausage breakfast casserole recipe is topping the casserole with the remaining cup of cheese. After the final dusting of cheese, you will cover the baking dish with tin foil and bake the casserole for 30 minutes. After 30 minutes, carefully pull the casserole from the oven and remove the tin foil, then bake the casserole for an additional ten minutes. If you're not sure if it's done, the cheese should be "melted and bubbly but not brown," per the recipe.

Once the sausage breakfast casserole is out of the oven and ready to eat, Johnson suggests topping it with green onions but only if green onions are your thing. You can really add any toppings you might love, as long as you serve this thing up warm. 

May we suggest salsa, hot sauce, avocado slices, or cilantro? We wouldn't be opposed to a bottle of ketchup on the table with this casserole either. It should freeze well if you want to make it and reheat for a future breakfast treat!