This casserole is the kind of comfort food that makes everyone pause mid-bite and smile. It’s rich and creamy, but has just enough spinach to feel balanced and satisfying. Ground sausage brings big, savory flavor without extra effort, and everything bakes together into a bubbly, golden dish.

Whether it’s a family dinner, a potluck, or weekend meal prep, this casserole is a reliable favorite you’ll make again and again.

What Makes This Recipe So Good

Big flavor, minimal effort: Seasoned sausage does most of the heavy lifting. You don’t need a long list of spices or complicated steps.
Creamy Alfredo goodness: A silky sauce coats every bite, and it bakes into the pasta so the texture stays luscious, not dry.
Greens that make sense: Spinach blends right into the casserole, adding color and nutrients without overpowering the dish.
Flexible and forgiving: Swap pasta shapes, use jarred or homemade Alfredo, and adjust cheese to your preference. It still turns out great.
Make-ahead friendly: Assemble ahead, refrigerate, then bake when you’re ready.
It reheats beautifully for lunches.

Close-up detail: Golden, bubbly Ground Sausage casserole just out of the oven

Shopping List

1 pound ground Italian sausage (mild or hot)
12 ounces pasta (penne, rigatoni, or rotini)
3 cups baby spinach, roughly chopped
2 cups Alfredo sauce (store-bought or homemade)
1/2 cup whole milk or half-and-half (to loosen the sauce)
1 small yellow onion, finely diced
3 cloves garlic, minced
1 cup shredded mozzarella
1/2 cup grated Parmesan (plus extra for serving)
2 tablespoons olive oil
1 teaspoon Italian seasoning
1/4 teaspoon red pepper flakes (optional)
Salt and black pepper
Nonstick spray or butter for the baking dish

How To Make My Ground Sausage Casserole

Cook the pasta: Bring a large pot of salted water to a boil. Cook pasta 1 to 2 minutes less than package directions for al dente. Drain and set aside.
Preheat the oven: Set to 375°F (190°C).
Grease a 9×13-inch baking dish with nonstick spray or butter.
Brown the sausage: Heat 1 tablespoon olive oil in a large skillet over medium-high heat. Add sausage, breaking it into crumbles, and cook until browned and no longer pink, about 6–8 minutes. Transfer to a plate, leaving some fat in the pan.
Sauté aromatics: Add remaining olive oil if needed.
Cook onion with a pinch of salt until soft and lightly golden, 4–5 minutes. Stir in garlic for 30 seconds until fragrant.
Wilt the spinach: Add chopped spinach and cook until just wilted, 1–2 minutes. Season with a little salt, pepper, Italian seasoning, and red pepper flakes if using.
Make it saucy: Reduce heat to low.
Stir in Alfredo sauce and milk (or half-and-half). Add the cooked sausage back to the pan and simmer lightly for 1–2 minutes. Taste and adjust seasoning.
Combine with pasta: In a large bowl, mix the pasta with the sauce mixture.
Fold in half the mozzarella and half the Parmesan.
Assemble the casserole: Spread the pasta mixture in the prepared baking dish. Top with remaining mozzarella and Parmesan.
Bake: Cover loosely with foil and bake for 15 minutes. Remove foil and bake another 10–12 minutes, until bubbly and lightly golden on top.
Rest and serve: Let the casserole rest for 5–10 minutes.
Garnish with extra Parmesan and cracked pepper if you like. Serve warm.

Cooking process grouns sausage casserole

Storage Instructions

Refrigerator: Cool completely, then store in an airtight container for up to 4 days.
Freezer: Wrap tightly and freeze for up to 2 months. Thaw overnight in the fridge before reheating.
Reheating: Reheat portions in the microwave with a splash of milk or water, covered, until hot.
For the whole dish, cover with foil and warm in a 325°F oven until heated through.
Make-ahead: Assemble up to 24 hours in advance and refrigerate. Add 5–10 minutes to the bake time if going straight from the fridge.

Benefits of This Recipe

Balanced comfort: Creamy pasta meets hearty protein and leafy greens in one pan.
Kid-friendly flavors: Mild sausage and a cheesy sauce keep it approachable for picky eaters.
Budget-conscious: Everyday ingredients stretch into multiple servings.
Meal prep win: Leftovers reheat well and taste just as good the next day.
Customizable: Works with different sausages, veggies, and cheeses without losing its charm.

Common Mistakes to Avoid

Overcooking the pasta: It continues cooking in the oven, so keep it a little firm after boiling.
Skipping seasoning: Taste the sauce before baking. Add salt, pepper, and a pinch of red pepper flakes if it needs a lift.
Dry casserole: Loosen the Alfredo with milk or half-and-half.
The pasta absorbs more liquid as it bakes.
Greasy result: If your sausage is very fatty, drain off some excess before adding the sauce.
Cheese overload on top: Too thick a layer can become rubbery. A balanced sprinkle melts and browns evenly.

Tasty top view final plate: Overhead shot of ground sausage casserole

Variations You Can Try

Chicken sausage: Swap in chicken or turkey sausage for a lighter option.
Mushroom boost: Sauté sliced cremini or portobello with the onions for extra umami.
Sun-dried tomato twist: Stir in chopped sun-dried tomatoes for tang and color.
Broccoli or peas: Add steamed broccoli florets or thawed peas for a veggie-packed version.
Three-cheese topping: Mix mozzarella with provolone and a bit of fontina for a gooey, stretchy top.
Garlic herb panko: Sprinkle buttered panko mixed with garlic powder and parsley over the top for crunch.
Gluten-free: Use your favorite gluten-free pasta and a gluten-free Alfredo.
Low-carb: Replace pasta with steamed cauliflower florets; bake until bubbly and tender.

FAQ’s For Ground Sausage Casserole

Can I use jarred Alfredo sauce?

Yes. Choose a brand you like and thin it slightly with milk or half-and-half so it coats the pasta well.

Taste and adjust seasoning, since some jars are mild.

What pasta shape works best?

Short, ridged shapes like penne, rigatoni, and rotini hold sauce well and bake evenly. Avoid very delicate shapes that can break apart.

How do I keep the casserole from drying out?

Undercook the pasta slightly, loosen the Alfredo with milk, and cover with foil for the first part of baking. Don’t skip the resting time, which helps the sauce settle.

Can I make this spicy?

Use hot Italian sausage and add red pepper flakes to taste.

A pinch of cayenne in the sauce also brings gentle heat.

Is there a good dairy-light option?

Use a lighter Alfredo if you prefer and add a splash of chicken broth. Keep a modest amount of cheese so it still feels creamy without being heavy.

Can I assemble and freeze before baking?

Yes. Assemble, cool, wrap tightly, and freeze.

Thaw in the fridge overnight, then bake covered until hot and bubbly, uncovering at the end to brown.

What can I serve with it?

A simple green salad with a bright vinaigrette and some garlic bread or roasted vegetables make a complete meal.

Wrapping Up

Ground Sausage & Spinach Alfredo Casserole is cozy, creamy, and low-stress—exactly what you want on a busy weeknight or when feeding a hungry crowd. It’s easy to customize, simple to make ahead, and always delivers big flavor. Keep these steps and tips on hand, and you’ll have a reliable dinner that earns repeat requests.