Name: Breakfast Sausage Egg 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); 2 cloves garlic (minced); 3 cups fresh spinach (90g); 2 large bell peppers (diced); ½ medium yellow onion (diced); Olive oil (as needed for sautéing); Salt and pepper (to taste); 12 large eggs; ½ cup milk (any, 120g); ½ cup shredded cheese (any flavor, divided, 56g)

There’s something incredibly comforting about a warm, savory breakfast waiting for you when the morning rush hits. This Breakfast Sausage Egg Casserole Recipe fits the bill perfectly — it’s hearty, packed with flavor, and makes mornings so much easier and joyful.

The image shows a glass baking dish with six square pieces of a baked egg dish. Each piece has multiple layers: a golden, slightly browned cheese topping with melted, textured surface, speckled with dark green spinach patches and small red pepper bits. Below the cheese layer, you can see a creamy, slightly crumbly egg mixture with visible red and green vegetable pieces, and a light base of what seems to be cooked mushrooms at the bottom. One square piece is being lifted gently by a silver spatula over a white marbled surface. The whole dish looks warm and appetizing. 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 Breakfast Sausage Egg Casserole Recipe
Top Tip
How to Serve Breakfast Sausage Egg Casserole Recipe
Make Ahead and Storage
Frequently Asked Questions:
Final Thoughts
Breakfast Sausage Egg Casserole Recipe

Why You'll Love This Recipe

Honestly, this breakfast casserole is a game changer for busy mornings or weekend brunches with friends. It blends sausage, veggies, eggs, and cheese into one delightful dish that’s as flexible as you want it to be.

Make-Ahead Magic: Prepare it the night before, pop it in the fridge, and wake up to a nearly ready breakfast.
Customizable Delight: Swap in your favorite veggies or cheeses to suit your taste buds and pantry.
Feeds a Crowd: Big family or guests? This casserole stretches to serve everyone without extra fuss.
Bonus Leftovers: It reheats beautifully — perfect for quick breakfasts throughout the week.

The image shows a close-up of a thick square slice of a baked egg dish on a white plate with a speckled pattern, resting on a white marbled surface with a green cloth nearby. The dish has about three layers: the top layer is a melted golden and light orange cheese with some darker browned spots, the middle layer is creamy and filled with small bits of green leafy vegetables and red pieces, and the bottom layer is firm and slightly textured. Behind the egg dish, there are roasted potato chunks with a crispy-looking golden brown surface. A silver fork lies beside the egg slice, partially resting on the plate. Photo taken with an iphone --ar 2:3 --v 7

Ingredients & Why They Work

Each ingredient plays a special role in making this Breakfast Sausage Egg Casserole Recipe both flavorful and satisfying. Using fresh veggies alongside hearty sausage and creamy eggs ensures a well-rounded dish that’s both nourishing and delicious.

Flat lay of a mound of raw fresh sausage meat, two peeled garlic cloves, a handful of fresh vibrant green spinach leaves, two large diced red and yellow bell peppers, half a medium yellow onion diced, twelve whole brown eggs with clean shells, a small white ceramic bowl of golden olive oil, a small white ceramic bowl of fresh milk, a small white ceramic bowl filled with shredded pale yellow cheese, coarse salt and black peppercorns scattered neatly in white ceramic dishes, 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: The star protein that gives the casserole savory richness. I usually use mild pork sausage, but spicy or turkey sausage works well too.
Olive Oil: Just a splash to sauté veggies without overpowering their natural flavors.
Garlic: Fresh minced garlic adds that delicious aromatic depth.
Spinach: Adds color, nutrients, and a subtle earthiness that balances the meat.
Bell Peppers: I find diced bell peppers bring a sweet crunch and vibrant color that brightens the whole dish.
Yellow Onion: Softened onions add natural sweetness and a mellow bite.
Salt & Pepper: Simple seasoning that enhances all the flavors without overwhelming.
Eggs: The binding hero that holds everything together with a fluffy, custardy texture.
Milk: Any kind you prefer — it lightens the eggs and keeps the bake tender.
Cheese: I love using a mix of cheddar and mozzarella. Cheese adds creaminess and that irresistible golden crust on top.

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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

This casserole is like a blank canvas that invites you to make it truly yours. I often swap spinach for kale or toss in mushrooms when I have them on hand. You can also mix up the cheese or add different herbs to keep things interesting.

Vegetarian Variation: Skip the sausage and double up on veggies like zucchini and mushrooms — I’ve done this when hosting my veggie-loving friends and it was a hit.
Spicy Kick: Add diced jalapeños or sprinkle crushed red pepper flakes into the egg mixture for a nice heat.
Make It Dairy-Free: Use plant-based milk and dairy-free cheese alternatives to keep things creamy without the dairy punch.
Hearty Extras: Toss in cooked hash browns or cubed potatoes for a more filling casserole perfect for brunch gatherings.

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

Step 1: Brown the Sausage for Maximum Flavor

Start by removing the casing from your sausage and browning it in a large skillet over medium heat. Even if your sausage is pre-cooked, I recommend browning it a bit — it adds a caramelized, savory depth that makes a big difference in the final dish. When it's nicely browned, spread it evenly in your greased casserole dish.

Step 2: Sauté the Veggies Just Right

In the same skillet, toss in a little olive oil if the pan looks dry. Quickly sauté the minced garlic, fresh spinach, diced bell peppers, and onions. Cook them until the peppers soften and the spinach wilts, about 6-7 minutes. Season lightly with salt and pepper toward the end so everything tastes bright and fresh.

Step 3: Mix It All in the Casserole Dish

Combine the cooked veggies with your browned sausage in the casserole dish. Give it a rough stir to distribute everything evenly, but don't overmix—you want pockets of sausage and veggies to create little flavor bursts.

Step 4: Whisk Eggs, Milk & Cheese

In a medium bowl, whisk together your large eggs, milk, and half the shredded cheese. This egg mixture is what will set nicely around the savory fillings. Pour it evenly over the sausage and veggies in the casserole, then sprinkle the remaining cheese on top for that irresistible cheesy crust.

Step 5: Bake or Refrigerate for Later

You have two options here: bake it immediately at 375ºF (191ºC) for about 45 minutes, or cover and refrigerate it for up to 24 hours if you'd like to prep ahead—rules for busy mornings! Make sure the edges start browning and the center is set before pulling it from the oven. Let it cool for 15 minutes, so it slices cleanly.

Top Tip

Over time, I’ve learned a few tricks that make this Breakfast Sausage Egg Casserole Recipe even better and easier to manage — here are my favorite tips to help you nail it every time.

Don’t Overcook the Eggs: Aim for a slightly jiggly center when you pull the casserole from the oven; it will set fully as it cools without turning rubbery.
Use a Non-Stick or Well-Greased Dish: This helps when you slice and serve so your casserole doesn’t stick to the pan—it happened to me once and the first slice came out a mess!
Customize Cheese Amounts: Start with less cheese if you’re watching fat or calories — you can always sprinkle a little more on top before baking for appearance.
Let It Rest: Don’t rush to serve right after baking; letting it rest makes slicing neater and flavors mingle better.

How to Serve Breakfast Sausage Egg Casserole Recipe

Breakfast Sausage Casserole - Serving Suggestion

Garnishes

I like topping my slices with a sprinkle of fresh chopped chives or parsley — it adds a fresh, pretty pop of color and a mild oniony flavor that balances the richness. Sometimes a dollop of sour cream or a drizzle of hot sauce takes it to the next level.

Side Dishes

This casserole pairs wonderfully with simple sides like fresh fruit salad, crispy hash browns, or even some buttery toast to scoop up any last bits. I also love serving it alongside roasted cherry tomatoes or a light green salad for a brunch spread.

Creative Ways to Present

For special occasions, I’ve baked this recipe in mini muffin tins — perfect for grab-and-go bites at brunch parties or potlucks. You can also layer it with sliced avocado and a sprinkle of smoked paprika for a colorful, festive look.

Make Ahead and Storage

Storing Leftovers

I store leftovers in an airtight container in the fridge for up to 5 days. Whenever I reheat a slice, I cover it lightly with a paper towel and zap it in the microwave for about a minute — it stays moist and delicious.

Freezing

This Breakfast Sausage Egg Casserole Recipe freezes wonderfully. I freeze it either unbaked or fully baked — just wrap it tightly in plastic wrap and foil. Before baking from frozen, thaw it overnight in the fridge for best texture.

Reheating

To reheat, I usually bake leftover slices at 350ºF (177ºC) for about 15–20 minutes, just enough to warm through and bring back that baked texture. If I’m in a hurry, the microwave works fine — just watch out not to overcook.

Frequently Asked Questions:

Can I prepare this Breakfast Sausage Egg Casserole Recipe ahead of time?

Absolutely! One of the best parts of this recipe is its flexibility. You can assemble the casserole the night before, refrigerate it, and then bake it fresh in the morning. It also freezes beautifully if you want to prep even further in advance.

What type of sausage works best in this casserole?

I prefer using bulk pork sausage for its flavor and texture, but fully cooked breakfast sausage or turkey sausage can also work well. Just brown the sausage for that extra rich flavor unless it’s already fully cooked.

Can I make this casserole vegetarian?

Yes! Simply omit the sausage and optionally add extra veggies like mushrooms, zucchini, or extra spinach. You can also add vegetarian sausage substitutes if you want some protein.

How long does this casserole keep in the fridge?

Stored in an airtight container, leftovers will keep well for up to 5 days in the refrigerator. Make sure to heat the portions thoroughly before eating.

Final Thoughts

I’ve made this Breakfast Sausage Egg Casserole Recipe countless times, and it never disappoints. It’s my go-to comfort food for busy mornings, cozy brunches, or feeding a hungry crowd with minimal stress. Give it a try—you’ll be amazed at how such simple ingredients can turn into a breakfast star that feels like a warm hug on a plate.