Name: Cheesy Italian Sausage Pasta Casserole Recipe
Prep time: 15 min
Cook time: 20 min
Total time: 1 h 20 min
Cuisine: Italian-American
Ingredients: 12 oz fusilli pasta; 1 lb bulk Italian sausage (sweet or hot); 1 medium onion diced; 3 cloves garlic minced; 1 green bell pepper seeded and diced; 8 oz cremini mushrooms quartered; 1 ½ tsp kosher salt; ½ tsp red pepper flakes; 2 tsp dried basil; 1 ½ tsp dried oregano; 3 15-oz cans strained tomatoes (or tomato sauce); 3 cups shredded mozzarella cheese; ½ cup (about 4 oz) sliced pepperoni

There's something utterly comforting about that perfect blend of gooey cheese, spicy sausage, and pasta all baked into one hearty dish. This Cheesy Italian Sausage Pasta Casserole Recipe is exactly that kind of soul-warming meal that turns an ordinary weeknight into a cozy celebration of flavors.

A black rectangular baking dish filled with baked spiral pasta covered in a thick layer of melted white cheese with a slightly golden finish, scattered with round, dark red pepperoni slices on top. The pasta is coated in a rich red tomato sauce with visible pieces of green bell pepper and brown mushrooms mixed throughout. The dish is placed on a white marbled surface, accompanied by two plain white plates stacked with two silver forks on the left, one plate holding a serving of the pasta, and a glass of dark red drink nearby. 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 Cheesy Italian Sausage Pasta Casserole Recipe
Top Tip
How to Serve Cheesy Italian Sausage Pasta Casserole Recipe
Make Ahead and Storage
Frequently Asked Questions:
Final Thoughts
Cheesy Italian Sausage Pasta Casserole Recipe

Why You'll Love This Recipe

I've made this casserole more times than I can count, partly because it’s so forgiving and partly because it never fails to impress anyone I serve it to. It brings together everyday ingredients in a way that feels a little special but doesn't require a culinary degree or hours in the kitchen.

Hearty and comforting: The blend of Italian sausage and melty mozzarella gives you those indulgent cheesy, meaty bites we all crave.
Simple and flexible: You can easily swap in your favorite pasta shape or add extra veggies without losing that classic flavor.
Feeds a crowd: This casserole stretches well, making it a perfect option for family dinners or potlucks.
Great leftovers: It reheats beautifully, so you’ll look forward to the next day’s lunch or dinner.

This image shows a close-up of a baked pasta dish in a black baking pan, placed on a white marbled surface. The dish has three visible layers: at the bottom is a rich, red tomato sauce with chunks of meat; the middle layer consists of tightly spiraled rotini pasta coated with the sauce; the top layer is a melted, creamy white cheese mixed with scattered slices of dark red pepperoni and small pieces of green bell pepper. The cheese has a stretchy, slightly browned texture that blends with the pasta and toppings, creating a warm and inviting look. Photo taken with an iphone --ar 2:3 --v 7

Ingredients & Why They Work

Every ingredient plays a role here, balancing bold and hearty flavors with comforting textures. Using bulk Italian sausage gives you that perfect spiced foundation without the fuss of casing, while fresh veggies add layers of flavor and color. For a seamless meal, grab good-quality shredded mozzarella — it melts like a dream and makes the whole dish sing.

Flat lay of cooked fusilli pasta in a neat mound, a small pile of raw sweet Italian sausage links, a medium whole yellow onion, three whole garlic bulbs with cloves intact, one fresh green bell pepper, whole cremini mushrooms grouped together, a small white ceramic bowl with coarse kosher salt, a small white bowl filled with red pepper flakes, two small white bowls containing dried basil and dried oregano leaves, three small white bowls holding smooth red tomato sauce, a small heap of shredded mozzarella cheese, and a small white bowl with neatly arranged sliced pepperoni, 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

Fusilli pasta: Its twisted shape catches sauce and cheese beautifully, ensuring each forkful is packed with flavor.
Bulk Italian sausage: Sweet or hot, it adds a wonderful savory punch that’s hard to beat.
Onion: Brings a mild sweetness that mellows once sautéed and balances the richness of the sausage.
Garlic: A must for that classic Italian depth — just the right amount to wake up the sauce.
Green bell pepper: Adds a fresh crunch and a subtle sweetness that pairs well with the sausage.
Cremini mushrooms: Earthy and tender, they add umami which melds perfectly with the meat and cheese.
Kosher salt: Heightens all the flavors, but be mindful not to overdo it.
Red pepper flakes: A hint of heat that adds excitement without overpowering the dish.
Dried basil & oregano: These classic Italian herbs bring that familiar flavor and aroma everyone loves.
Strained tomatoes (or tomato sauce): Creamy and smooth, they create a luscious sauce base that clings to every pasta twist.
Shredded mozzarella cheese: Melts into a gooey blanket that turns this casserole into pure comfort food.
Sliced pepperoni: Sprinkled in layers for extra bursts of spicy, meaty flavor and that irresistible crisp edge once baked.

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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

One of the best things about this Cheesy Italian Sausage Pasta Casserole Recipe is how easy it is to tailor. I love adding extra veggies in the fall, like zucchini or spinach, for a twist. You can also swap pepperoni for sliced olives or cooked pancetta if you want to mix up the flavors.

Variation: Once, I made it with spicy chorizo instead of Italian sausage—deliciously smoky and perfect if you like bold heat.
Vegetarian: Omit the sausage and pepperoni, and add more mushrooms, bell peppers, and maybe some artichoke hearts for a veggie-packed version.
Gluten-free: Use your favorite gluten-free pasta to keep this dish accessible without sacrificing flavor.
Cheese swap: Mixing mozzarella with a bit of provolone or fontina can add a little extra richness.

Step-by-Step: How I Make Cheesy Italian Sausage Pasta Casserole Recipe

Step 1: Cook the Pasta to Al Dente Perfection

Start by boiling your fusilli pasta in salted water until it's just al dente—firm but tender. This is key because the pasta will finish cooking in the oven, and you don't want it too mushy. Drain it well and set it aside. Trust me, taking this step seriously makes a big difference in the texture.

Step 2: Brown the Italian Sausage

While the pasta cooks, heat a large skillet over medium heat and add your bulk Italian sausage. Break it up into bite-sized pieces with a wooden spoon or spatula. Let it brown evenly, stirring occasionally for about 6-8 minutes. You want a nice sear for flavor but avoid drying it out.

Step 3: Sauté the Veggies & Build the Sauce

Next, toss in your diced onion, minced garlic, diced green bell pepper, and quartered cremini mushrooms right into the sausage pan. Cook everything till the onions soften and the veggies release their aromas, about 4-6 minutes. Then stir in salt, red pepper flakes, dried basil, and oregano to infuse those classic Italian flavors. Pour in the strained tomatoes and let it simmer gently for 3-4 minutes—this helps everything marry beautifully.

Step 4: Layer and Assemble the Casserole

Mix the meat sauce with the cooked pasta and half the pepperoni slices right in your mixing bowl. Then pour half the noodles into your greased 9x13 baking dish, sprinkle with half the mozzarella cheese, and add the rest of the noodles. Finish with the remaining cheese and top with the rest of your pepperoni. This layering helps the cheese melt beautifully within the casserole.

Step 5: Bake to Cheesy, Bubbling Goodness

Cover your dish with foil and bake at 350°F for 25 minutes. Then remove the cover and bake for another 15-20 minutes, or until the cheese is bubbling and starting to brown at the edges. This final bake gives you that irresistible crispy top that makes casseroles so satisfying.

Top Tip

Over the years, I've learned a few things that help this Cheesy Italian Sausage Pasta Casserole Recipe come out perfect every single time. These little tricks save you time and stress.

Don't overcook the pasta: Cooking it just to al dente before baking prevents mushiness in the final dish.
Brown your sausage well: This adds depth of flavor and keeps the meat juicy versus simply boiling it.
Simmer the sauce slightly: Gives the tomatoes and spices a chance to blend flavors before baking.
Use good-quality shredded cheese: This ensures a smooth melt and that lovely gooey texture everyone loves.

How to Serve Cheesy Italian Sausage Pasta Casserole Recipe

cheesy Italian sausage - Serving Suggestion

Garnishes

I love to sprinkle freshly chopped basil or flat-leaf parsley over the top just before serving — it adds a pop of color and fresh flavor that cuts the richness nicely. A light dusting of grated Parmesan also works wonders if you want to wow guests.

Side Dishes

This casserole stands beautifully on its own but pairs perfectly with a crisp green salad tossed in lemon vinaigrette. Garlic bread or a warm crusty baguette also make great companions, perfect for mopping up any leftover sauce.

Creative Ways to Present

For a special occasion, I've baked individual portions in mini cast iron skillets — it makes for a charming presentation that's both rustic and personal. You could also add layers of roasted veggies between the pasta to create a vibrant layered look.

Make Ahead and Storage

Storing Leftovers

Once cooled, I tightly cover leftovers with foil or plastic wrap and store them in the refrigerator. They usually last well for up to 3 days while keeping their flavor and texture.

Freezing

This casserole freezes beautifully. I portion it into airtight containers or freeze a whole dish wrapped generously in foil and plastic to avoid freezer burn. When I'm ready to eat it, I just thaw overnight in the fridge before reheating.

Reheating

When reheating, I cover the casserole with foil to prevent it from drying out and warm it in the oven at 350°F until heated through, usually about 20-25 minutes. For single servings, the microwave works fine, but keep an eye on it to avoid overcooking.

Frequently Asked Questions:

Can I use other types of pasta for this casserole?

Absolutely! While fusilli is great for holding sauce, penne, rigatoni, or even rotini will work well. Just make sure to cook the pasta al dente as it will bake in the sauce later.

Can I make this casserole ahead of time?

Yes! This Cheesy Italian Sausage Pasta Casserole Recipe can be assembled a day ahead and stored covered in the refrigerator. When you're ready, bake it as directed—just add a few extra minutes to the baking time if coming straight from the fridge.

Is it possible to reduce the fat in this recipe?

You can definitely lean this recipe out by using turkey or chicken sausage instead of traditional pork Italian sausage. Also, trimming excess fat during browning and using part-skim mozzarella will help reduce calories without sacrificing flavor too much.

Can I make this gluten-free?

Absolutely! Simply swap in your favorite gluten-free pasta to keep the casserole gluten-free. Just make sure it's cooked al dente before baking to avoid sogginess. The rest of the ingredients are naturally gluten-free.

Final Thoughts

This Cheesy Italian Sausage Pasta Casserole Recipe holds a special place in my kitchen because it’s comfort food that effortlessly feels like a treat. Every time I make it, from browning the sausage to that satisfying cheese pull, it reminds me how simple ingredients can come together to make something truly delightful. I’m excited for you to try it and tweak it to your liking – it always turns into a crowd-pleaser.