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Spaghetti Squash Casserole Recipe

Spaghetti Squash Casserole

Wholesome Cove
This spaghetti squash casserole recipe turns a humble winter vegetable into a hearty, cheesy baked dinner. Roasted spaghetti squash strands stand in for noodles, layered with a savory beef and marinara sauce, then finished under a blanket of melted mozzarella and parmesan.
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Prep Time 20 minutes
Cook Time 50 minutes
Total Time 1 hour 10 minutes
Course Main Course
Cuisine American, Italian
Servings 6 servings
Calories 365 kcal

Equipment

  • Sharp chef's knife - for cutting the squash in half safely
  • Large rimmed baking sheet - for roasting the squash halves
  • Large oven-safe skillet or sauté pan - for browning the beef and building the sauce
  • 9x13 inch baking dish - for assembling and baking the casserole
  • Large mixing bowl - for combining the squash strands with the sauce
  • Two forks - for shredding the squash into strands
  • Instant-read meat thermometer - to confirm the beef is fully cooked
  • Aluminum foil - for covering the dish during baking

Ingredients
  

  • 1 large spaghetti squash - about 3 to 4 lbs / 1.4 to 1.8 kg
  • 2 tablespoons extra virgin olive oil - divided
  • 1 lb lean ground beef - 450g, 85/15 works well
  • 1 small yellow onion - diced
  • 3 cloves garlic - minced
  • 1 jar marinara sauce - 24 oz / 680g, preferably a thick variety
  • 1 can San Marzano diced tomatoes - 14.5 oz / 411g
  • 1 tablespoon Italian seasoning
  • ½ teaspoon crushed red pepper flakes - optional
  • Salt and black pepper - to taste
  • ½ cup ricotta cheese - 115g
  • 1 cup grated Parmesan cheese - 90g, divided
  • 1½ cups shredded mozzarella cheese - 170g
  • 2 tablespoons fresh basil - chopped, plus more for garnish
  • 2 tablespoons fresh parsley - chopped

Instructions
 

  • Preheat oven to 400°F (200°C). Cut spaghetti squash in half lengthwise, scoop out seeds, drizzle cut sides with 1 tablespoon olive oil, and season with salt and pepper.
  • Place squash cut side down on a baking sheet and roast for 35-45 minutes until tender. Let cool for 10 minutes, then scrape flesh into strands with a fork and transfer to a large bowl.
  • While squash roasts, heat remaining 1 tablespoon olive oil in a large skillet over medium heat. Cook onion for 3-4 minutes until softened, then add garlic and cook for 30 seconds until fragrant.
  • Add ground beef to the skillet, breaking it up as it cooks. Cook for 6-8 minutes until no pink remains and internal temperature reaches 160°F (71°C). Drain excess fat.
  • Stir in marinara sauce, diced tomatoes, Italian seasoning, red pepper flakes, salt, and pepper. Reduce heat to low and simmer for 10 minutes until slightly thickened.
  • Reduce oven temperature to 375°F (190°C). In the bowl with shredded squash, combine half the meat sauce, ricotta, and half the Parmesan. Stir until evenly combined.
  • Grease a 9x13 inch baking dish. Spread the squash mixture evenly in the dish. Top with remaining meat sauce, then sprinkle with mozzarella and remaining Parmesan.
  • Cover tightly with foil and bake for 20 minutes. Remove foil and bake for 15-20 minutes more until cheese is melted and golden in spots and sauce is bubbling.
  • Let rest for 10 minutes before serving. Garnish with fresh basil and parsley.

Notes

  • Salt the squash before roasting: This draws out a little extra moisture before the squash ever meets the sauce.
  • Don't rush the roasting time: Squash that isn't fully tender will be harder to shred and will taste starchy instead of pasta-like.
  • Let the squash cool before shredding: Working with it too hot makes the strands mushy instead of distinct.
  • Use a thick marinara, not a thin one: A watery sauce combined with the squash's natural moisture can make the casserole soupy.
  • Drain the beef well: Extra grease left in the pan adds unwanted liquid to the finished dish.
  • Let the casserole rest before slicing: Ten minutes out of the oven helps everything set so it holds together when served.
  • Pat the squash strands dry: If they seem especially wet after roasting, pat them with paper towels, especially if your squash was on the larger side.
  • Make ahead: Assemble the entire casserole up to a day in advance and refrigerate before baking. Add about 10 extra minutes to the covered baking time if baking cold.
  • Freezer friendly: Freeze before baking for up to 2 months, or freeze after baking and cooling completely. Thaw overnight in the refrigerator before reheating.
  • Vegetarian option: Omit the ground beef and add extra vegetables like mushrooms, zucchini, or spinach to the sauce instead.

Nutrition

Serving: 1servingCalories: 365kcalCarbohydrates: 16gProtein: 27gFat: 23gSaturated Fat: 10gPolyunsaturated Fat: 2gMonounsaturated Fat: 9gCholesterol: 70mgSodium: 720mgPotassium: 520mgFiber: 3gSugar: 8gVitamin A: 12IUVitamin C: 15mgCalcium: 25mgIron: 15mg
Keyword cheesy squash bake, gluten free dinner, low carb casserole, spaghetti squash casserole
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