Name: Spaghetti Squash Casserole (Lasagna Style) Recipe
Prep time: 20 min
Cook time: 1 h 5 min
Total time: 1 h 25 min
Cuisine: Italian-American
Ingredients: 2 small spaghetti squash; 1 tbsp olive oil; 1/2 tsp kosher salt; 1/2 tsp ground pepper; 1 lb Italian sausage; 1 lb ground beef; 1 medium sweet onion, diced to ½ inch; 4 cloves garlic, minced; 1 (6 oz) can tomato paste; 28 oz crushed tomatoes; 1 tsp kosher salt; 1/2 tsp ground pepper; 2 tsp Italian seasoning; 2 tbsp chopped basil, divided; 2 cups ricotta cheese; 2 cups shredded mozzarella cheese, divided; ½ cup parmesan cheese

Jump to Recipe· 4.3 from 45 reviews

If you are craving a delicious, comforting dish that brings the heartiness of lasagna with a low-carb twist, then this Spaghetti Squash Casserole (Lasagna Style) Recipe is going to become your new favorite dinner. Roasted spaghetti squash strands layered with a rich meat sauce, creamy ricotta, and melty mozzarella combine to create a luscious casserole that satisfies all your Italian food dreams without the traditional noodles. It’s warm, flavorful, and a brilliant way to enjoy the textures and tastes of lasagna while sneaking in some extra veggies.

Ingredients You’ll Need

A close-up view of a large orange pot with a white inside, filled with browned ground meat mixed with small pieces of cooked onion scattered evenly throughout. The cooked meat looks crumbly and granular with a mix of light brown and slightly darker brown colors, while the diced onions are white and translucent. The pot sits on a white marbled surface. photo taken with an iphone --ar 4:5 --v 7

All the ingredients here are simple and easy to find, but they each play a vital role in making this dish shine. From the naturally sweet and tender spaghetti squash to the savory meat sauce and creamy cheeses, everything combines perfectly for an unforgettable casserole.

2 small spaghetti squash: The star vegetable that cleverly stands in for pasta noodles with its naturally stringy texture.

1 tbsp olive oil: Used to coat the squash before roasting, adding richness and helping it caramelize slightly.
1/2 tsp kosher salt: Enhances the natural flavors of the squash and meat sauce.
1/2 tsp ground pepper: Provides a subtle kick and balances the seasoning.

1 lb Italian sausage: Adds bold, spiced flavor and a juicy texture to the meat sauce.
1 lb ground beef: Gives depth and meaty richness to the sauce.
1 medium sweet onion (diced to ½”): Offers sweetness and a gentle bite to complement the meat.

4 cloves garlic: Brings aromatic warmth that infuses the entire sauce.
1 6-oz can tomato paste: Intensifies tomato flavor and thickens the sauce.
28 oz crushed tomatoes: Forms the lush, tangy base of the sauce that ties everything together.

1 tsp kosher salt: Seasoning for the sauce to boost all the flavors.
2 tsp Italian seasoning: A fragrant blend of herbs that gives the sauce a classic Italian touch.
2 tbsp chopped basil (divided): Freshness that brightens the casserole and adds vibrant green color.

2 cups ricotta cheese: Creamy and mild, balancing the savory meat and tangy tomato flavors.
2 cups shredded mozzarella cheese: Melts beautifully over the casserole for gooey, cheesy goodness.
½ cup parmesan cheese: Adds a salty, nutty kick that elevates every bite.

How to Make Spaghetti Squash Casserole (Lasagna Style) Recipe

A clear glass bowl filled with a thick, creamy white mixture that has a slightly grainy texture, with some small clumps and soft lumps visible throughout. A silver spoon is partly buried in the mixture, its handle resting on the edge of the bowl. The bowl sits on a white marbled surface. photo taken with an iphone --ar 4:5 --v 7

Step 1: Roast the Spaghetti Squash

Preheat your oven to 425°F and line a baking sheet with parchment paper to make cleanup a breeze. Slice the spaghetti squash lengthwise and scoop out the seeds—this part is always a bit fun, like opening a little edible treasure chest. Rub the flesh all over with olive oil and sprinkle with salt and pepper for that essential seasoning layer. Place the halves cut side down on the baking sheet and roast. Around 30-35 minutes for smaller squash is perfect, but larger ones might need up to 45 minutes until the flesh is tender and starting to cave in. Let the squash cool for about five minutes before gently raking a fork through the flesh to fluff out those beautiful strands.

Step 2: Prepare the Meat Sauce

While the squash is roasting its magic, start cooking your meat sauce. Heat a large Dutch oven or deep skillet over medium-high heat, then brown the Italian sausage and ground beef together, breaking them into small crumbles. This usually takes about 10 to 12 minutes. Once the meat is no longer pink, toss in the diced onion and sauté until softened, about 5 to 6 minutes, so you develop a sweet and savory base. Then add minced garlic and stir it in for just a minute, releasing that signature fragrance. Stir in tomato paste and cook it for 2-3 minutes—this step really crushes any canned flavor and brings a deeper tomato taste. Next, pour in crushed tomatoes, add salt, pepper, and Italian seasoning, and let everything simmer for 15 minutes. Finish by stirring in the flaked spaghetti squash and one tablespoon of fresh chopped basil for a hint of brightness in every bite.

Step 3: Mix the Cheeses

In a small bowl, combine the ricotta cheese, half of the shredded mozzarella, and the parmesan cheese. This cheesy mixture will create creamy pockets throughout the casserole that perfectly complement the tomatoey meat and tender squash strands.

Step 4: Assemble the Casserole

Grab a casserole dish and spread a third of the spaghetti squash and meat mixture evenly across the bottom. Dollop half of your ricotta cheese mixture gently over this layer, then add another third of the squash and meat sauce on top. Repeat by adding the remaining ricotta mixture and finish with the last third of the squash mixture. Top everything off by sprinkling the rest of the mozzarella cheese generously across the surface—this will melt into a bubbly, golden crust that’s absolutely irresistible.

Step 5: Bake to Perfection

Cover your casserole dish with foil and bake at 400°F for 20 minutes to meld all those delicious flavors. Then remove the foil and bake for an additional 5 minutes or until the cheese on top is lightly browned and the casserole is bubbling like a dream. Finally, garnish liberally with the remaining chopped fresh basil—it adds just the right touch of color and herbal aroma to finish this dish beautifully.

How to Serve Spaghetti Squash Casserole (Lasagna Style) Recipe

Garnishes

A generous sprinkle of fresh basil adds a pop of bright green and aromatic freshness that contrasts wonderfully with the rich, cheesy casserole. Sometimes, a little extra parmesan or a drizzle of good olive oil can elevate the presentation and flavor even more.

Side Dishes

Complement this casserole with a crisp green salad tossed in a tangy vinaigrette to cut through the richness. Garlic bread or a basket of warm, crusty rolls also pair beautifully, providing that classic Italian meal experience.

Creative Ways to Present

To amp up your dinner party wow factor, serve the casserole in individual ramekins for personalized portions. Alternatively, layer it in a clear glass dish so guests can admire the beautiful layers of spaghetti squash, meat sauce, and cheese before digging in.

Make Ahead and Storage

Storing Leftovers

Leftover Spaghetti Squash Casserole (Lasagna Style) Recipe keeps wonderfully in the fridge for up to 4 days when stored in an airtight container. It makes for a hearty lunch or a quickly reheated dinner that tastes almost as good as freshly baked.

Freezing

This casserole freezes very well, making it a perfect dish to prepare in advance. Let it cool completely, then wrap tightly with foil or place in a freezer-safe container. It can be frozen for up to 3 months and thawed overnight in the fridge before reheating.

Reheating

For best results, reheat individual portions in the microwave or warm the entire casserole in a 350°F oven until heated through and bubbly, about 20-25 minutes. If frozen, allow it to thaw thoroughly first for even warming and to maintain the perfect texture.

FAQs

Can I use ground turkey or chicken instead of beef and sausage?

Absolutely! Ground turkey or chicken will work well for a lighter version of this casserole. Just brown the meat thoroughly and season it well to keep the flavors robust.

Is it necessary to roast the spaghetti squash before assembling?

Yes, roasting softens the squash and brings out its natural sweetness, which is essential to mimic the texture and flavor of noodles in this casserole.

Can I make this recipe vegetarian?

Definitely! Swap out the meat for sautéed mushrooms, lentils, or a plant-based meat substitute to keep it hearty and flavorful while being meat-free.

What can I use instead of ricotta cheese if I don’t have any?

You can substitute ricotta with cottage cheese or a blend of cream cheese and mozzarella to maintain creaminess in the casserole.

How spicy is this casserole? Can I adjust the heat?

The heat level is mild to medium thanks to the Italian sausage and seasoning, but you can easily dial it up or down by choosing spicy or sweet sausage and adjusting the amount of black pepper or adding red pepper flakes.

Final Thoughts

This Spaghetti Squash Casserole (Lasagna Style) Recipe is a brilliant way to enjoy all the cozy, cheesy goodness of traditional lasagna with a lighter, veggie-packed twist. It’s an absolute crowd-pleaser that’s perfect for weeknight dinners or special gatherings. I can’t wait for you to try it and see just how satisfying healthy comfort food can be!