Name: Easy Sausage Breakfast Casserole Recipe
Prep time: 20 min
Cook time: 45 min
Total time: 1 h 5 min
Cuisine: American
Ingredients: 10 to 12 ounces sausage (casing removed); olive oil (as needed for sautéing); 2 cloves garlic (minced); 3 cups fresh spinach (90g); 2 large bell peppers (diced); ½ medium yellow onion (diced); salt and pepper (to taste); 12 large eggs; ½ cup milk (any type, 120g); ½ cup shredded cheese (any flavor, 56g, divided)

Imagine waking up to the smell of warm sausage, melted cheese, and sautéed veggies all baked into a fluffy egg casserole—that’s exactly what this Easy Sausage Breakfast Casserole Recipe delivers. It’s my go-to for busy mornings when you want something hearty, comforting, and totally hands-off once it’s in the oven.

This image shows a golden brown baked egg dish cut into squares, with one square being lifted by a silver spatula. The dish has three visible layers: the top layer is melted cheese with a bubbly, slightly crispy texture in shades of orange and yellow; the middle layer shows cooked spinach and small pieces of red pepper scattered throughout a creamy, light yellow egg mixture; the bottom layer is a slightly browned crust. The dish is in a clear glass baking dish, placed on a white marbled surface. Photo taken with an iphone --ar 2:3 --v 7

Jump to:

Why You'll Love This Recipe
Ingredients & Why They Work
Make It Your Way
Step-by-Step: How I Make Easy Sausage Breakfast Casserole Recipe
Top Tip
How to Serve Easy Sausage Breakfast Casserole Recipe
Make Ahead and Storage
Frequently Asked Questions:
Final Thoughts
Easy Sausage Breakfast Casserole Recipe

Why You'll Love This Recipe

I absolutely love how this casserole balances rich sausage with bright veggies and fluffy eggs—plus it’s so flexible. This recipe has saved many rushed mornings and made brunches feel just a little more special around my kitchen table.

Simple Ingredients: You likely have everything on hand already, making it perfect for last-minute meals.
Hands-Off Prep: Once it’s in the oven, you’re free to focus on getting ready or entertaining guests.
Make-Ahead Friendly: Prep it the night before or freeze it for a no-stress breakfast later in the week.
Customizable to Your Taste: Swap veggies, cheese, or sausage to fit your family’s favorites or dietary needs.

A white plate on a white marbled surface holds two square pieces of a layered egg dish with a shiny golden-yellow top mixed with orange and green spots from melted cheese, spinach, and red peppers. The layers inside show a creamy yellow egg base with visible bits of vegetables and cheese in a soft texture. To the left of the egg squares, there is a pile of cubed roasted potatoes with a light brown crust and some red potato pieces, creating a crunchy look. A silver fork rests on the plate near the egg dish, and a green cloth is underneath the plate. Photo taken with an iphone --ar 2:3 --v 7

Ingredients & Why They Work

The magic really comes down to layering hearty sausage with tender spinach, peppers, and onions, all bound together with eggs and melty cheese. These flavors and textures complement each other so well, and I love how they make every bite satisfying without feeling heavy. When shopping, choose a flavorful sausage you enjoy and fresh veggies to keep it vibrant.

Flat lay of a heap of raw sausage meat without casing, two peeled garlic cloves, a small bunch of fresh spinach leaves, two diced red and yellow bell peppers, half a diced yellow onion, a clean salt and pepper shaker, a cluster of twelve whole large eggs with smooth shells, a small white ceramic bowl with olive oil, a small white ceramic bowl of milk, and a small white ceramic bowl holding shredded cheese, all arranged symmetrically on a clean white marble surface, soft natural light, photo taken with an iPhone, professional food photography style, fresh ingredients, white ceramic bowls, no bottles, no duplicates, no utensils, no packaging --ar 2:3 --v 7 --p m7354615311229779997

Sausage: Opt for fresh or fully cooked sausage; browning it enhances flavor and adds a lovely texture.
Olive Oil: Used for sautéing veggies, but sometimes the sausage renders enough fat so you can skip adding more.
Garlic: Adds a warm, aromatic punch that makes the whole casserole more inviting.
Fresh Spinach: It wilts beautifully in the pan and adds freshness and color.
Bell Peppers: I like a mix of colors for sweetness and crunch that balance the richness.
Yellow Onion: Sautéed until soft for depth of flavor without overpowering the dish.
Salt and Pepper: Simple seasonings to bring out the best in all ingredients.
Eggs: The protein-packed base that binds everything into a fluffy, tender casserole.
Milk: Adds moisture and richness to the eggs; any kind works for you.
Shredded Cheese: I usually split between mixing some in and sprinkling some on top for gooey goodness and a golden crust.

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Note: You'll find the complete list of ingredients, along with their exact measurements, in the printable recipe card at the bottom of this post.

Make It Your Way

I love tweaking this casserole depending on what’s in season or what’s in my fridge. You can easily swap veggies or cheese to suit your taste buds or dietary needs. The best part? It always turns out delicious!

Variation: One time, I swapped bell peppers for sautéed mushrooms and added a handful of sun-dried tomatoes — the earthiness with the sausage was divine.
Dietary tweaks: Use turkey sausage or a plant-based sausage alternative and swap regular milk for almond or oat milk for a lighter or dairy-free version.
Cheese mix-up: Try a sharper cheddar, pepper jack for a little spice, or even feta for a tangy twist.
Extra add-ins: Toss in some diced cooked potatoes or black beans for more substance.

Step-by-Step: How I Make Easy Sausage Breakfast Casserole Recipe

Step 1: Brown the sausage for flavor and texture

Start by heating a skillet over medium heat and browning your sausage. Even if it’s fully cooked, I like giving it a little sizzle to deepen its flavor and crisp up some edges. Use a spoon to break it into crumbles as it cooks, then spread it evenly in your prepared casserole dish. This forms the savory base every other ingredient builds on.

Step 2: Sauté your veggies until tender and fragrant

Using the same skillet, add a splash of olive oil if needed. Toss in the minced garlic, diced onions, bell peppers, and fresh spinach. Sauté for about 6-7 minutes until the veggies soften and the spinach wilts. Season with salt and pepper near the end to bring out their natural flavors without overwhelming. This mix adds freshness and a bit of sweetness to balance the rich sausage.

Step 3: Combine meat and veggies, then mix eggs and cheese

Stir the cooked veggie mixture into the browned sausage in your casserole dish, distributing everything evenly. In a separate bowl, whisk together your eggs, milk, and half of the shredded cheese. Pour this silky egg mixture over the meat and veggies, then sprinkle the remaining cheese on top. Finish with a pinch of salt and pepper for good measure.

Step 4: Bake and let it rest

Pop your casserole into a 375ºF (191ºC) oven and bake for around 45 minutes. You’ll know it’s done when the edges turn golden brown and a knife inserted comes out clean. Let it cool for at least 15 minutes before serving—that rest time helps it set, making it easier to cut and enjoy.

Top Tip

From my many attempts making this casserole, a few simple tips have made a big difference in getting the best results—these are the little things I swear by.

Don’t skip browning the sausage: Even pre-cooked varieties benefit from a quick sizzle to build flavor and texture.
Vegetable timing: Sauté veggies just until they’re tender but not mushy; overcooking makes the casserole watery.
Use room-temperature eggs & milk: They combine more evenly, giving you a fluffier egg bake.
Let it rest: Waiting 15 minutes after baking is key — it helps everything set and makes cutting neat slices much easier.

How to Serve Easy Sausage Breakfast Casserole Recipe

sausage breakfast casserole - Serving Suggestion

Garnishes

I usually top mine with a little chopped fresh parsley or green onions for a pop of color and fresh flavor. A dollop of sour cream or a drizzle of hot sauce adds a nice tang and spice that wake up the dish perfectly.

Side Dishes

Serve this casserole alongside crispy hash browns, fresh fruit, or even a light mixed green salad to balance the richness. It pairs wonderfully with a simple glass of fresh orange juice or your favorite morning coffee.

Creative Ways to Present

For brunch gatherings, I like to bake this casserole in a pretty ceramic dish and surround it with small bowls of toppings like sliced avocado, salsa, or pickled jalapeños. It makes serving interactive and more festive—your guests love it!

Make Ahead and Storage

Storing Leftovers

Once cooled, I cover leftovers tightly with plastic wrap or foil and store them in the fridge for up to five days. It’s great for quick breakfasts or lunches during the week.

Freezing

I often freeze the casserole unbaked — wrapped well with plastic and foil — which is a total lifesaver. When I’m ready, I thaw it overnight in the fridge and bake as usual. It tastes just as fresh as when first made!

Reheating

To warm up leftovers, I microwave individual portions for about 1-2 minutes or reheat the whole dish in a 350ºF oven until heated through. Covering loosely with foil helps keep it moist while reheating.

Frequently Asked Questions:

Can I use different types of sausage in this casserole?

Absolutely! This Easy Sausage Breakfast Casserole Recipe is super flexible—try spicy, sweet, turkey, or plant-based sausage depending on your preference. Just make sure to adjust cooking time if your sausage needs to be fully cooked first.

Can I prepare the casserole the night before?

Yes! One of the best things about this recipe is that you can assemble it the night before, cover it tightly, and refrigerate. In the morning, simply pop it in a preheated oven and bake as directed.

What is the best way to reheat leftover casserole?

For the best texture and flavor, reheat individual portions in the microwave for 1-2 minutes or warm the entire dish in a 350ºF oven covered with foil until heated through.

Can I freeze this breakfast casserole?

Yes, you can freeze this casserole either unbaked or baked. For unbaked, cover tightly with plastic wrap and foil and freeze up to 2 months. Thaw overnight before baking. For baked casserole, freeze portions and reheat as needed.

Final Thoughts

This Easy Sausage Breakfast Casserole Recipe holds a special place in my kitchen because it’s reliable, flexible, and delightful every single time. It’s the kind of meal that brings comfort but still feels like a treat, whether for family breakfasts or casual brunches with friends. Give it a try—you might just find your new favorite morning dish!