Sausage Breakfast Casserole is one of the best I’ve ever tried. Fresh eggs, cheddar cheese, bread, sausage links, and a creamy mushroom “country gravy” topping.
Is it just me or does pretty much everybody eat some sort of breakfast casserole on Christmas morning? My mom started serving this version many years ago, she called it Sausage Fondue. Now the recipe card is fragile and faded but this classic will live on in our family for generations to come. I’ve tried many breakfast casseroles for comparison and though I’ve found a few others we really like, we come back to this one for a truly comforting recipe that hits all the important points.
One of my friends described this dish as “perfectly custardy and delicious”. The combination of the egg mixture and just the right amount of bread create the perfect custard-creamy texture she’s talking about. Let me tell you how I put it together and what makes this one so special.
Tips for making Sausage Breakfast Casserole
First it’s important to use the right bread and the right amount of bread. I’ve tested French bread and even whole grain, but for this one day, use good old fashioned white sandwich bread. Some people recommend using day-old bread and I do to, if you have it. But I’ve also used fresh-from-the-grocer fluffy bread with great results, so use what you have. After you grease your 9 x 13-inch pan, cut the bread into smaller cubes, I like to make them about 1/2-inch thick. And over the years, I’ve cut back little by little until six (or even five) slices is just enough for a good bottom structure. You just want enough to cover the bottom of the dish.
After the bread is cubed and placed into the buttered pan, add your favorite cheese- anything from mild or even sharp cheddar, Monterey jack, and shown here is Colby which is a great combination of cheddar AND jack!
The sausage links are pretty much whatever you like but a couple of notes that help this recipe- Skinless sausage makes for a better “bite”, and you can buy precooked but I still sauté them a bit to add some color/flavor that baking won’t accomplish. Most of our tasters agree that a little sausage in every bite was preferred so I cut my links into fourths to cover the casserole.
Next comes what makes this casserole creamy-tasty. Eight fresh eggs which is a perfect ratio to the bread, cheese, and sausage, some milk, onion salt, dried mustard, and cayenne. Whisk very well and then pour over the entire casserole before placing in the fridge. I love to make the recipe up until this point the night before serving but have also let it sit in the fridge for up to 24 hours and for as little as four hours. Your main goal here is to let the egg mixture fully incorporate with the bread before baking.
So friends, I’ve found that this next step is what really sets this recipe apart from others I’ve tried. Just before baking, pour a mixture of condensed cream of mushroom soup, milk, and minced garlic over the Sausage Breakfast Casserole. A few friends of mine are shocked! that I would use condensed soup, but during the holidays, easy steps are helpful and I’ve tried to make this casserole a time or two using homemade cream of mushroom soup and to be honest, it’s not worth the added effort for such a busy time of year.
The casserole gets baked low and slow (1 hour in a 325F degree oven) until the egg mixture poofs up and the top becomes golden (the casserole will calm back down after you remove it from the oven).
Can Sausage Breakfast Casserole be made ahead?
This casserole is incredibly versatile; I’ve made it just four hours ahead of baking and as long as 24 hours beforehand. You want to assemble and refrigerate the sausage breakfast casserole long enough that the eggs soak fully into the bread before baking. So, if you really can’t wait, I think baking about 30 minutes after assembly would even be fine.
Can Sausage Breakfast Casserole be frozen?
I prefer to make this recipe the day before serving for the ultimate freshness but if you really want to make one for freezing, here are the instructions:
- TO FREEZE: Do not bake the casserole before freezing. When the sausage breakfast casserole is fully assembled (except for the mushroom soup potion) wrap with a layer of plastic wrap and a layer of foil. Place in your freezer for up to 3 months.
- TO HEAT: Remove casserole from freezer. Remove plastic wrap and foil. Allow casserole to fully thaw. When thawed bake as directed in the original method; 1 1/2 hours in a 300F degree oven until eggs are fully cooked through and set in the center. The top should become golden brown.
How to reheat Sausage Breakfast Casserole
Since you might not be hosting a full-press Christmas party this year, you may have a few leftover pieces of the casserole. Store leftovers in an airtight container for a day and reheat in a 300F degree oven until warmed through. I don’t recommend reheating the casserole in the microwave.
What to serve with Sausage Breakfast Casserole
This casserole is full of all the great, savory flavors you want in a breakfast- just add a side of fruit, some breakfast pastries and it’s a full meal. If you’re really wanting to vamp up the buffet, add some country hash browns, yogurt, and juice or mimosas. My family likes to kind of go casserole crazy and we serve the Sausage Breakfast Casserole alongside a French Toast Casserole or Pumpkin Pie Breakfast Bake, crispy bacon and potatoes of some kind.
Gluten-free Breakfast Casserole
You can definitely make this recipe without the bread though it’ll be more like a frittata and assembling ahead of time isn’t really necessary then.
Vegetarian Breakfast Casserole
Leaving out the sausage will make for a fabulous vegetarian casserole! If you like, top the finished casserole with a handful of diced bell pepper or green onions before serving for added color and crunch.
Sausage Breakfast Casserole
Make ahead portion of recipe
- 10-12 links sausage I prefer skinless links, you can also use bulk sausage, about ½ to ¾ pound.
- 6 slices bread favorite sandwich bread, french bread or any thicker sliced bread
- 2 cups cheddar, Colby, Monterey Jack or your favorite melting cheese grated
- 8 large eggs
- 2 ½ cups whole milk
- 1 tsp ground mustard
- ½ tsp onion salt
- 1/8 tsp cayenne pepper
Add next morning just before baking
- 1 cup condensed cream of mushroom soup or homemade mushroom soup if desired. See recipe note
- ½ cup whole milk
- 1 clove garlic minced
- ¼ tsp black pepper
Just before serving
- 2 tbsp chopped fresh parsley or chives
Make ahead portion of recipe
- Cook your sausage links until barely pink inside and browned nicely on the outside. If the outsides are nicely browned, this adds flavor and color that baking won't necessarily achieve. (You can use "precooked" links if you like and skip the precooking of the sausage.) Remove sausage from the pan and place on a plate to cool slightly, then cut into bite-size pieces. If using bulk sausage, break them up into bite-size pieces before cooking (thirds or fourths). Don't overcook the sausage.
- Grease a 9x13 baking dish with butter or cooking spray. Cut bread into cubes about ½" to 1" in size or to your liking, but smaller is better. Arrange the bread cubes in the bottom of the baking dish.
- Sprinkle grated cheese over the bread. Top with the sausage pieces.
- Crack the eggs into a large bowl and add the 2 ½ cups of milk, ground mustard, onion salt, and cayenne pepper. Mix well, using a fork. Pour the egg mixture over the casserole, pouring to coat all of the bread.
- Cover the casserole with plastic wrap or foil and refrigerate overnight (at least 6 hours).
The next morning before baking
- Preheat oven to 325°F and place oven rack at center position. Take casserole out of the refrigerator and remove covering.
- Combine 1 cup of cream of mushroom soup with ½ cup milk and whisk with a fork, reserving the extra condensed soup. Add the minced garlic, salt and pepper, and stir well. Pour this mixture over the casserole. Place the leftover soup in the refrigerator while for now.
- Bake uncovered for 1 hour or until the top is nicely golden and the eggs look set. During the last 15 minutes of cooking, add the reserved mushroom soup to 1/2 cup of milk and heat on the stove or in the microwave, making sure to not let it boil. Keep heated until casserole is ready to serve, then you may serve the additional sauce to pour over (this step is optional).
- Remove casserole from oven, sprinkle with the fresh parsley and cut into individual servings. Six to eight pieces, depending on portion sizes you want.
- Any leftovers can be covered and refrigerated for two days, then reheated in oven (preferable) or microwave. The casserole is good reheated but is best when served right out of the oven.
- This is one recipe where using regular white sandwich bread provides the best results. I've made it with healthy, whole grain bread as well and it is tasty but the texture will be less "silky". Whatever bread you use, be sure to cut into small pieces as indicated in the recipe, about 1/2" to 1" in size.
- During the step where you add the cream of mushroom soup, if using homemade mushroom soup or soup that isn't condensed, skip adding the 1/2 cup milk and increase the amount of homemade or non-condensed soup by 1/2 cup.
- This recipe is delicious without the sausage for a vegetarian option. If making vegetarian, I would sprinkle diced green and red bell peppers over the top just before serving.
- If you're worried about sodium in this recipe, reduce the amount of sausage and instead of 1 cup of cream of mushroom soup, use 1/2 cup of the condensed soup and 1/2 cup milk. There will be less of the "gravy" but the casserole will still be great.