Instant Pot Cheesy Spaghetti Squash

Category: Perfect Side Dishes to Complete Any Meal

Spaghetti squash transforms into a tender, flavorful base when cooked in the Instant Pot for just 7 minutes. After pressure cooking, the strands of squash are mixed with fresh spinach, creamy ricotta, oregano, and a touch of red pepper flakes, creating a vibrant filling. This mixture returns to the squash shells, which are then topped with rich marinara, fresh mozzarella, and Parmesan cheese. A quick broil melts the cheeses perfectly, resulting in a warm, satisfying dish with a hint of herbal freshness from chopped parsley.

A woman wearing a chef's hat and apron.
Created By Sarah
Last updated on Tue, 28 Oct 2025 23:32:16 GMT
A stack of spaghetti squash with cheese on top. Save
A stack of spaghetti squash with cheese on top. | sarahmeal.com

This cheesy spaghetti squash made in the Instant Pot is perfect for those nights when you want something comforting but fast. The squash cooks in just seven minutes, which is a game changer compared to the usual long bake times, and the cheesy topping feels like a lighter twist on lasagna. It’s versatile enough to be served as a meal on its own or dressed up in different styles like burrito boats.

I first made this when I was craving lasagna but wanted to avoid pasta and it quickly became a weeknight favorite in my house. The ease of cooking and the way the squash strands soak up the sauce makes it so satisfying.

Ingredients

  • Water: One cup to steam the squash in the Instant Pot
  • Spaghetti squash: One medium halved and seeds removed for quick cooking and that fun noodle texture
  • Kosher salt: For seasoning that brings out natural sweetness in the squash
  • Freshly ground black pepper: To add a little bite
  • Baby spinach: Two cups for freshness and a boost of greens
  • Ricotta: One and a half cups which keeps the filling creamy and rich
  • Dried oregano: One teaspoon adds an herby depth that complements the cheese
  • Crushed red pepper flakes: Quarter teaspoon for a gentle spicy kick
  • Marinara: One and a half cups for that tangy tomato flavor that ties everything together
  • Fresh mozzarella: Half a pound thinly sliced to melt beautifully on top
  • Parmesan: Quarter cup freshly grated for a salty, nutty finish
  • Parsley: Freshly chopped to garnish, adding color and a fresh note

Ingredients

When getting your squash look for firm skin with no soft spots for the best roasting texture. Fresh mozzarella is key here because it melts better than the pre-shredded kind.

Step-by-Step Instructions

Sauté the Aromatics:
Place the trivet inside your Instant Pot and pour in one cup of water. Season the spaghetti squash halves with kosher salt and freshly ground black pepper. Place the squash halves carefully on the trivet then lock the lid and set your Instant Pot to Pressure Cook on High for seven minutes. When cooking is done, do a quick release according to your machine’s instructions and carefully open the lid. Use tongs to remove the hot squash from the pot and let it cool until easy to handle.
Prepare the Filling:
While the squash cools, preheat your oven to broil. Using a fork, scrape the spaghetti squash flesh carefully into a large bowl, separating the strands for that noodle-like texture. Add the baby spinach, ricotta, dried oregano, and crushed red pepper flakes into the bowl and toss everything together until well combined. These ingredients form a creamy, flavorful filling.
Assemble and Broil:
Spoon the cheesy spinach mixture back into the empty squash skins to serve as edible bowls. Then spoon marinara sauce over the top, making sure to cover the filling. Lay thin slices of fresh mozzarella all over and sprinkle the Parmesan cheese as the final touch. Place the stuffed squash shells on a baking sheet and broil in the oven until the cheese melts and starts getting bubbly which should take about five minutes. Once done, garnish with freshly chopped parsley and serve immediately.
A plate of spaghetti squash with cheese. Save
A plate of spaghetti squash with cheese. | sarahmeal.com

One of my favorite parts is the contrast between the tender strands of the squash and the creamy melted cheese on top. I remember making this for friends who were skeptical about spaghetti squash and they all asked for seconds. The cheesy topping is really what wins everyone over.

Storage Tips

Leftovers can be stored in an airtight container in the fridge for up to three days. To reheat, brush a little olive oil on top, cover loosely with foil, and warm in the oven to keep the cheese melty. Avoid microwaving if you want to preserve the texture.

Ingredient Substitutions

If you don’t have ricotta, cream cheese or cottage cheese blended smooth can work as a substitute. For the fresh mozzarella, shredded mozzarella can be used but the texture won’t be quite the same. Use fresh or frozen spinach, just be sure to squeeze out excess water if using frozen.

Serving Suggestions

Serve with a light green salad dressed with lemon vinaigrette to balance the richness of the cheese. Garlic bread or a crusty baguette pairs perfectly if you want to add some crunch. This also makes a nice side dish alongside grilled chicken or fish.

Cultural Context

Spaghetti squash has become popular as a low-carb pasta alternative in many health-conscious kitchens. Using the Instant Pot speeds up the traditional bake time and makes it very accessible. Cheese and tomato sauce as a topping is inspired by classic Italian lasagna layers but here presented in a lighter vegetable-forward way.

Pro Tips

  • Always remove the seeds from the squash for easier shredding and better texture
  • Don’t skip letting the squash cool enough to handle before scraping out the strands or you risk burning your fingers
  • Broil with close attention because cheese can go from melty to burnt quickly

Common Recipe Questions

→ How do you prepare the spaghetti squash for cooking?

Slice the spaghetti squash in half lengthwise and remove the seeds before seasoning with salt and pepper.

→ What is the best method to cook spaghetti squash quickly?

Using an Instant Pot on High Pressure for 7 minutes cooks the squash perfectly tender without drying it out.

→ Can I substitute the cheeses used in this dish?

Yes, while ricotta, mozzarella, and Parmesan provide creamy and melty textures, feel free to use similar cheeses like fontina or gruyere for variations.

→ What can I add to enhance the flavor of the filling?

Fresh herbs like oregano and a pinch of crushed red pepper flakes elevate the flavor, while spinach adds a fresh, nutritious touch.

→ How long should the stuffed squash be broiled?

Broil for about 5 minutes, or until the cheese is melted and bubbly with slight browning on top.

→ Can I prepare this dish ahead of time?

Yes, you can prepare the filling and squash shells in advance and broil just before serving for best texture and warmth.

Instant Pot Cheesy Spaghetti Squash

Spaghetti squash cooked fast with spinach, ricotta, and melty cheeses for a savory meal.

Preparation Time
10 minutes
Cook Time
12 minutes
Total Duration
22 minutes
Created By: Sarah

Recipe Category: Side Dishes

Level of Difficulty: Simple

Cuisine Style: American

Servings Yield: 2 Portion Size (2 stuffed spaghetti squash halves)

Diet Preferences: Low-Carb Option, Vegetarian-Friendly, Gluten-Free Option

What You'll Need

→ Liquids

Ingredient 01 240 ml water

→ Produce

Ingredient 02 1 medium spaghetti squash, halved, seeds removed
Ingredient 03 2 cups (60 g) baby spinach
Ingredient 04 Freshly chopped parsley, for garnish

→ Dairy

Ingredient 05 360 g ricotta cheese
Ingredient 06 225 g fresh mozzarella, thinly sliced
Ingredient 07 25 g freshly grated Parmesan cheese

→ Pantry

Ingredient 08 Kosher salt, to taste
Ingredient 09 Freshly ground black pepper, to taste
Ingredient 10 1 tsp dried oregano
Ingredient 11 1/4 tsp crushed red pepper flakes
Ingredient 12 360 ml marinara sauce

How to Make It

Instruction 01

Place the trivet in the Instant Pot and pour in the water. Season the spaghetti squash halves with salt and pepper. Place them on the trivet inside the Instant Pot, lock the lid, and set to Pressure Cook on High for 7 minutes. Perform a quick release according to the manufacturer's instructions, then remove the squash and let it cool until manageable.

Instruction 02

Preheat the oven to broil. Using a fork, scrape the flesh of the spaghetti squash into a large bowl, preserving the squash skins. Add the baby spinach, ricotta, dried oregano, and crushed red pepper flakes to the bowl and mix until combined. Spoon the filling back into the reserved squash skins. Top with marinara sauce, mozzarella slices, and grated Parmesan.

Instruction 03

Arrange the stuffed squash halves on a large baking sheet. Broil in the preheated oven until the cheese is melted and bubbly, about 5 minutes. Remove from oven, garnish with freshly chopped parsley, and serve immediately.

Additional Tips

  1. Allow the squash to cool enough to handle safely before scraping the strands to prevent burns.

Essential Tools

  • Instant Pot or electric pressure cooker
  • Fork for shredding spaghetti squash
  • Oven broiler
  • Large baking sheet

Allergy Details

Always review ingredient labels for allergens, and consult a professional if you're unsure.
  • Contains dairy; not suitable for lactose-intolerant individuals

Nutritional Breakdown (per serving)

These nutritional details are for informational purposes and shouldn't replace medical advice.
  • Calories: 420
  • Fat Content: 28 grams
  • Carbohydrate Content: 22.5 grams
  • Protein Content: 18 grams