The Mushroom Bolognese Spaghetti Squash Casserole is a cheesy, comforting, and wholesome vegetarian dish that’s gluten-free and low-carb. With a rich mushroom-based Bolognese sauce layered over roasted spaghetti squash and topped with three cheeses, this casserole is perfect for a cozy dinner or meal prep. It’s a flavorful twist on classic lasagna, combining healthful ingredients with indulgent textures.
Full Recipe:
Ingredients
For the Mushroom Bolognese Sauce:
- 2 tbsp olive oil
- ½ large onion, finely chopped
- 8 oz baby bella or crimini mushrooms, quartered
- 5 cloves garlic, minced
- 1 tsp rosemary (fresh or dried)
- 2 tsp dried oregano
- 2 tsp paprika
- ½ tsp red pepper flakes (optional)
- 1 tsp sea salt
- 1 (28 oz) can crushed tomatoes (undrained)
- 2 tbsp fresh basil, chopped
For the Spaghetti Squash Casserole:
- 1 large spaghetti squash, roasted
- 1 ½ cups mozzarella cheese, grated
- ¼ cup Parmesan cheese, grated
- ⅓ cup ricotta cheese
Directions
- Roast the Spaghetti Squash:
Preheat the oven and roast the spaghetti squash. Refer to preferred roasting methods or follow standard instructions. - Prepare the Mushroom Bolognese Sauce:
- Heat olive oil in a large sauté pan over medium heat. Add the chopped onion and sauté for 8 minutes until fragrant and softened.
- Stir in the mushrooms and garlic, cooking for 3–5 minutes. Add rosemary, oregano, paprika, red pepper flakes, and salt. Cook for 2 minutes.
- Add the crushed tomatoes and bring to a gentle boil. Lower the heat to a simmer, cover, and cook for 30 minutes (longer for deeper flavor). Uncover and simmer for 10 more minutes to thicken. Stir in basil and set aside.
- Assemble the Casserole:
- Preheat the oven to 400°F and grease a 9-inch casserole dish.
- Spread the roasted spaghetti squash in the dish and season with sea salt.
- Pour the mushroom Bolognese sauce over the squash and layer with mozzarella, Parmesan, and ricotta cheeses.
- Bake the Casserole:
Bake for 30–45 minutes on the center rack until the cheese is golden and the sauce bubbles. Allow the casserole to sit for 30 minutes before serving to let the flavors meld and excess liquid settle.
Nutrients (Per Serving)
- Calories: 350 kcal
- Carbohydrates: 23g
- Protein: 19g
- Fat: 21g
- Fiber: 6g
- Sugar: 11g
This hearty dish is perfect for a family dinner or meal prep, and it’s even more delicious the next day. Enjoy the rich, cheesy goodness guilt-free! 🍴
Why You’ll Love This Recipe
Rich, Comforting Flavors
This casserole is a true crowd-pleaser, blending the earthy richness of mushrooms with the tangy sweetness of crushed tomatoes and fragrant herbs like oregano, rosemary, and basil. The cheeses on top add layers of creaminess and a golden, bubbly finish, making it irresistibly comforting.
Healthy and Wholesome
By swapping traditional pasta for spaghetti squash, this dish is lower in carbs and calories without sacrificing flavor or texture. Spaghetti squash provides a slightly sweet and nutty base that perfectly complements the savory Mushroom Bolognese sauce. The addition of fresh vegetables and heart-healthy olive oil makes this casserole both nourishing and satisfying.
Perfect for Meal Prep
This casserole is not only delicious fresh out of the oven but also reheats beautifully, making it ideal for meal prep. Store it in individual portions for a quick and satisfying lunch or dinner throughout the week.
Key Ingredients and Their Benefits
Spaghetti Squash: The Pasta Alternative
Spaghetti squash is a fantastic low-carb alternative to traditional pasta. Once roasted, its flesh transforms into tender, noodle-like strands that are perfect for soaking up the flavors of the Mushroom Bolognese sauce. It’s rich in vitamins A, B6, and C, as well as fiber, which aids digestion and promotes satiety.
Mushrooms: The Star of the Sauce
Mushrooms are the base of this vegetarian Bolognese sauce, providing a meaty texture and a deep umami flavor. Baby bella or crimini mushrooms work wonderfully in this recipe, but feel free to mix in shiitake or portobello mushrooms for added depth. They’re packed with antioxidants, B vitamins, and selenium, supporting overall health.
Tomatoes: A Tangy and Sweet Base
Crushed tomatoes are a staple in this recipe, lending acidity, sweetness, and a rich, saucy consistency to the Bolognese. Tomatoes are high in lycopene, an antioxidant that supports heart health and helps fight inflammation.
Cheese Trio: A Layer of Indulgence
The combination of mozzarella, Parmesan, and ricotta adds creaminess, nuttiness, and a golden crust to the casserole. These cheeses not only enhance the flavor but also provide protein and calcium, making the dish even more satisfying.
Herbs and Spices: The Flavor Boost
The use of fresh basil, rosemary, oregano, and paprika infuses the dish with bold Mediterranean-inspired flavors. Red pepper flakes are optional but add a touch of heat that complements the other spices beautifully.
How to Customize the Casserole
Make It Vegan
For a vegan version, replace the cheeses with plant-based alternatives, such as cashew ricotta or vegan mozzarella. Use nutritional yeast for a cheesy, nutty flavor, and ensure your crushed tomatoes and other ingredients are vegan-certified.
Add Protein
If you’d like to include more protein, add cooked lentils, crumbled tofu, or even ground turkey or chicken for a non-vegetarian option. These can be incorporated into the Bolognese sauce during the cooking process.
Incorporate More Vegetables
This casserole is a versatile canvas for additional veggies. Consider adding sautéed spinach, roasted bell peppers, zucchini slices, or eggplant for even more flavor and nutrition.
Switch Up the Cheeses
While mozzarella, Parmesan, and ricotta are classic, you can experiment with other cheeses like Gruyère, Fontina, or goat cheese for a different flavor profile.
Tips for the Best Casserole
- Roast the Spaghetti Squash Properly Roasting spaghetti squash is crucial for achieving the right texture. Avoid overcooking it to prevent it from becoming mushy. A properly roasted squash should yield tender, slightly firm strands.
- Cook the Sauce Slowly Simmering the Mushroom Bolognese sauce for a longer time allows the flavors to meld and intensify. For a richer taste, let it cook for an hour or more if you have the time.
- Drain Excess Liquid Both spaghetti squash and the sauce can release liquid as they cook. To avoid a watery casserole, drain the squash strands well and simmer the sauce until it thickens.
- Let It Rest Allow the casserole to rest for at least 15–30 minutes after baking. This helps the flavors meld and prevents the casserole from being too liquidy when sliced.
Serving Suggestions
This Mushroom Bolognese Spaghetti Squash Casserole is a complete meal on its own, but you can pair it with:
- A Side Salad: A simple green salad with a lemon vinaigrette complements the richness of the casserole.
- Garlic Bread: For a more indulgent meal, serve with a side of crusty garlic bread.
- Roasted Vegetables: Oven-roasted Brussels sprouts, asparagus, or carrots make excellent accompaniments.
- Wine Pairing: A glass of light red wine, such as Pinot Noir, or a crisp white wine, like Sauvignon Blanc, pairs beautifully with the flavors.
Why You Should Try This Recipe
This casserole is more than just a meal—it’s a flavorful journey that combines indulgence with wholesome ingredients. Whether you’re feeding a family, entertaining guests, or simply treating yourself to a comforting dinner, this dish delivers. It’s easy to make, customizable to your preferences, and packed with nutrients that leave you feeling satisfied and nourished.
Conclusion
The Mushroom Bolognese Spaghetti Squash Casserole is a testament to how delicious and versatile vegetarian cooking can be. By combining the natural sweetness of spaghetti squash with the hearty richness of a mushroom-based sauce and the creamy indulgence of melted cheese, this recipe creates a dish that’s both comforting and nutritious. Its gluten-free, low-carb nature makes it a suitable option for various dietary preferences without compromising flavor.
Print
Mushroom Bolognese Spaghetti Squash Casserole
Description
The Mushroom Bolognese Spaghetti Squash Casserole is a cheesy, comforting, and wholesome vegetarian dish that’s gluten-free and low-carb. With a rich mushroom-based Bolognese sauce layered over roasted spaghetti squash and topped with three cheeses, this casserole is perfect for a cozy dinner or meal prep. It’s a flavorful twist on classic lasagna, combining healthful ingredients with indulgent textures.
Ingredients
For the Mushroom Bolognese Sauce:
- 2 tbsp olive oil
- 1/2 large onion, finely chopped
- 8 oz baby bella or crimini mushrooms, quartered
- 5 cloves garlic, minced
- 1 tsp rosemary (fresh or dried)
- 2 tsp dried oregano
- 2 tsp paprika
- 1/2 tsp red pepper flakes (optional)
- 1 tsp sea salt
- 1 (28 oz) can crushed tomatoes (undrained)
- 2 tbsp fresh basil, chopped
For the Spaghetti Squash Casserole:
- 1 large spaghetti squash, roasted
- 1 1/2 cups mozzarella cheese, grated
- 1/4 cup Parmesan cheese, grated
- 1/3 cup ricotta cheese
Instructions
- Roast the Spaghetti Squash:
Preheat the oven and roast the spaghetti squash. Refer to preferred roasting methods or follow standard instructions. - Prepare the Mushroom Bolognese Sauce:
- Heat olive oil in a large sauté pan over medium heat. Add the chopped onion and sauté for 8 minutes until fragrant and softened.
- Stir in the mushrooms and garlic, cooking for 3–5 minutes. Add rosemary, oregano, paprika, red pepper flakes, and salt. Cook for 2 minutes.
- Add the crushed tomatoes and bring to a gentle boil. Lower the heat to a simmer, cover, and cook for 30 minutes (longer for deeper flavor). Uncover and simmer for 10 more minutes to thicken. Stir in basil and set aside.
- Assemble the Casserole:
- Preheat the oven to 400°F and grease a 9-inch casserole dish.
- Spread the roasted spaghetti squash in the dish and season with sea salt.
- Pour the mushroom Bolognese sauce over the squash and layer with mozzarella, Parmesan, and ricotta cheeses.
- Bake the Casserole:
Bake for 30–45 minutes on the center rack until the cheese is golden and the sauce bubbles. Allow the casserole to sit for 30 minutes before serving to let the flavors meld and excess liquid settle.
- Category: Dinner
