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Vegetarian spaghetti squash casserole recipe

Vegetarian Spaghetti Squash Casserole Recipe

Print Recipe
Prep Time 15 mins
Cook Time 30 mins
Total Time 45 mins
Servings 6 servings
Calories 282


  • 1 spaghetti squash prepared
  • 1/2 tsp dried basil
  • 1/4 tsp ground thyme
  • 1 Tbsp olive oil
  • 1 onion diced
  • 2 cloves garlic minced
  • 1 1/2 cups mushrooms sliced
  • 1 cup zucchini sliced
  • 1 cup green bell pepper diced
  • 1 1/2 cups marinara sauce
  • 3/4 cup mozzarella cheese grated
  • 1/4 cup Parmesan cheese grated
  • 3/4 cup mozzarella cheese grated
  • 1/4 cup panko breadcrumbs


  • Preheat the oven to 375 degrees.
  • Prepare the spaghetti squash according to the recipe.
  • Run a fork along the inside of the prepared squash to create spaghetti-like strands, scoop it into a medium-sized mixing bowl. Stir in basil and thyme then set aside.
  • Heat olive oil in large sauté pan over medium heat. Add onion and garlic, stirring frequently for 5 minutes, until onion begins to turn translucent. Add mushrooms, zucchini and green bell pepper. Sauté for 1 minute more then remove from heat.
  • Place half of the spaghetti squash in the bottom of a 2-qt casserole dish. Spread half of the sautéed vegetables over the squash then half of the marinara sauce over vegetables. Top with a layer of mozzarella cheese. Add the remaining squash. Layer the remaining vegetables then pour the remaining marinara sauce on top.
  • Mix the Parmesan cheese, mozzarella cheese and panko breadcrumbs together in a small bowl. Sprinkle over the entire dish.
  • Cover the dish with aluminum foil then bake for 20 minutes. Uncover and continue baking an additional 10 minutes or until hot and bubbly. Serve and enjoy immediately!


Need this dish to be gluten-free? Simply omit the panko!


Calories: 282kcal | Carbohydrates: 27g | Protein: 14g | Fat: 15g | Saturated Fat: 6g | Polyunsaturated Fat: 3g | Monounsaturated Fat: 6g | Cholesterol: 18mg | Sodium: 837mg | Potassium: 706mg | Fiber: 4g | Sugar: 12g