Butternut Squash, Mushroom & Spinach Lasagna Recipe

Introduction

This Butternut Squash, Mushroom & Spinach Lasagna is a comforting, flavorful twist on the classic Italian dish. Packed with roasted vegetables and creamy cheese fillings, it’s perfect for a cozy weeknight dinner or special occasion. The no-boil noodles make assembly easy and the creamy cauliflower sauce adds a unique richness.

Ingredients

• 1 pound frozen cauliflower florets
• 1 cup almond milk
• 8 ounces reduced fat cream cheese (plain)
• 1 teaspoon dijon mustard
• ¼ teaspoon ground nutmeg
• ¼ teaspoon salt
• ¼ teaspoon black pepper
• 1-2 tablespoons olive oil (extra virgin)
• 1 ½ pounds (about 5 cups cubed) butternut squash (peeled, seeded, cubed)
• ½ teaspoon garlic powder
• ½ teaspoon smoked paprika
• ½ teaspoon black pepper
• ½ teaspoon oregano
• 1 ½ teaspoon salt (divided)
• 4 cups fresh spinach
• 4-6 cloves fresh garlic (crushed)
• 1 small onion (diced)
• 1 ½ pounds baby bella mushrooms (sliced)
• 1 pound part skim ricotta cheese
• 1 large egg
• 1 tablespoon garlic (minced)
• ½ teaspoon ground nutmeg
• ½ teaspoon salt
• ½ teaspoon black pepper
• 12-16 ounces no-boil lasagna noodles
• 3 cups low-moisture, part skim mozzarella cheese (shredded)
• ½ cup asiago cheese (grated)
• 6-8 leaves fried sage (optional)

Instructions

1. Step 1: Preheat the oven to 425°F (220°C).
2. Step 2: For the cream sauce, place cauliflower florets and almond milk in a large pot. Cover and cook over medium-high heat for 12-15 minutes until cauliflower is very soft.
3. Step 3: Add cream cheese, salt, pepper, and Dijon mustard to the pot. Stir until the cream cheese melts.
4. Step 4: Using an immersion blender, blend the cauliflower and cream cheese mixture until smooth. Add more almond milk if the sauce is too thick. Stir in nutmeg, then remove from heat and set aside.
5. Step 5: Drizzle olive oil on a large baking sheet and spread cubed butternut squash evenly. Sprinkle garlic powder, smoked paprika, black pepper, oregano, and 1 teaspoon salt over the squash. Toss to coat.
6. Step 6: Roast the squash for 15 minutes. Remove, toss again, then roast for another 13 minutes until soft and slightly crispy.
7. Step 7: Gently mash the roasted squash with a potato masher. Top with fresh spinach and return to the oven for 2-3 minutes to wilt the spinach.
8. Step 8: Heat a little olive oil in a large saucepan over medium-high heat. Add crushed garlic and diced onion, sautéing for 4-5 minutes until onions are translucent.
9. Step 9: Add sliced mushrooms and cook 3-5 minutes until they develop color. Sprinkle with ½ teaspoon salt and combine with the squash and spinach mixture. Toss everything together and remove from heat.
10. Step 10: For the ricotta filling, whisk together ricotta, egg, minced garlic, nutmeg, salt, and black pepper in a large bowl. Refrigerate until assembly.
11. Step 11: Reduce oven temperature to 375°F (190°C).
12. Step 12: Grease a 13 x 9-inch casserole dish. Spread 1/3 of the cauliflower cream sauce evenly on the bottom.
13. Step 13: Layer 1/3 of the no-boil lasagna noodles over the sauce, breaking pieces if needed to cover the base completely.
14. Step 14: Add half of the ricotta mixture, then half of the vegetable filling. Sprinkle with 1 cup mozzarella cheese.
15. Step 15: Repeat layers with 1/3 of the noodles, remaining ricotta, remaining vegetable filling, and another cup of mozzarella.
16. Step 16: Top with the remaining noodles, spread the rest of the cream sauce over them, and sprinkle with the last cup of mozzarella cheese.
17. Step 17: Cover tightly with foil and bake for 40 minutes. Remove foil, top with asiago cheese, and bake for an additional 15-20 minutes. Broil for 2 minutes if you want a golden top.
18. Step 18: Garnish with fresh parsley or optional fried sage leaves and crushed red pepper flakes. Season with cracked black pepper and serve hot.

Tips & Variations

• Use fresh sage leaves fried in olive oil for a fragrant, crispy garnish that adds an earthy flavor.
• Swap almond milk for any plant-based or dairy milk you prefer to adjust creaminess.
• For extra richness, add a layer of shredded parmesan cheese.
• Make it vegan by substituting ricotta with tofu ricotta and using vegan cheese options.
• To save time, roast the butternut squash a day ahead.

Storage

Store leftover lasagna tightly covered in the refrigerator for up to 4 days. Reheat individual portions in the microwave or rewarm the entire dish covered with foil at 350°F (175°C) until heated through, about 20-25 minutes. You can also freeze the unbaked assembled lasagna for up to 3 months; thaw overnight in the fridge before baking.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I use regular lasagna noodles instead of no-boil?

Yes, but you will need to boil them according to package instructions before layering. Adjust the sauce amount slightly to keep the dish moist.

Is this recipe gluten-free?

The recipe as written uses regular no-boil lasagna noodles which contain gluten. To make it gluten-free, substitute with gluten-free no-boil noodles.

Butternut Squash, Mushroom & Spinach Lasagna Recipe

Print Recipe

★★★★★

4.9 from 113 reviews

This Butternut Squash, Mushroom & Spinach Lasagna is a delicious vegetarian twist on classic lasagna, featuring roasted butternut squash, sautéed mushrooms, and fresh spinach layered with creamy cauliflower-based sauce and ricotta filling. Perfectly seasoned and topped with mozzarella and asiago cheese, it’s a hearty and comforting dish that satisfies with a healthy vegetable boost.

• Author: Lila
• Prep Time: 20 minutes
• Cook Time: 1 hour 15 minutes
• Total Time: 1 hour 35 minutes
• Yield: 8 servings 1x
• Category: Main Dish
• Method: Baking
• Cuisine: Italian
• Diet: Vegetarian

Ingredients

Scale 1x2x3x

Cream Sauce

• 1 pound frozen cauliflower florets
• 1 cup almond milk
• 8 ounces reduced fat cream cheese (plain)
• 1 teaspoon dijon mustard
• ¼ teaspoon ground nutmeg
• ¼ teaspoon salt
• ¼ teaspoon black pepper

Vegetable Filling

• 1–2 tablespoons olive oil (extra virgin)
• 1 ½ pounds (about 5 cups cubed) butternut squash (peeled, seeded, cubed)
• ½ teaspoon garlic powder
• ½ teaspoon smoked paprika
• ½ teaspoon black pepper
• ½ teaspoon oregano
• 1 ½ teaspoon salt (divided)
• 4 cups fresh spinach
• 4–6 cloves fresh garlic (crushed)
• 1 small onion (diced)
• 1 ½ pounds baby bella mushrooms (sliced)

Ricotta Filling

• 1 pound part skim ricotta cheese
• 1 large egg
• 1 tablespoon garlic (minced)
• ½ teaspoon ground nutmeg
• ½ teaspoon salt
• ½ teaspoon black pepper

Assembly

• 12–16 ounces no-boil lasagna noodles
• 3 cups low-moisture, part skim mozzarella cheese (shredded)
• ½ cup asiago cheese (grated)
• 6–8 leaves fried sage (optional)

Instructions

1. Preheat oven: Preheat your oven to 425°F (218°C) to prepare for roasting the butternut squash and baking later.
2. Make the Cream Sauce: In a large pot, add the frozen cauliflower florets and almond milk. Cover and cook over medium-high heat for 12-15 minutes until the cauliflower is very soft and mushy. Add in the reduced fat cream cheese, dijon mustard, salt, and black pepper. Stir until the cream cheese melts completely. Use an immersion blender to blend the mixture until smooth, adding more milk if it’s too thick. Stir in the nutmeg, then remove from heat and set aside.
3. Prepare the Vegetable Filling: Drizzle a large baking sheet with olive oil and spread the cubed butternut squash on it. Season with garlic powder, smoked paprika, black pepper, oregano, and 1 teaspoon of salt. Toss to coat the squash evenly. Roast for 15 minutes, then remove and toss the squash. Roast for another 13 minutes or until the squash is soft and slightly crisp on the edges. Remove from oven and gently mash the squash using a potato masher. Top the mashed squash with fresh spinach and return to the oven for 2-3 minutes until the spinach wilts.
4. Sauté mushrooms and onions: In a large saucepan over medium-high heat, add a little olive oil and cook crushed garlic and diced onion for 4-5 minutes until translucent. Add sliced baby bella mushrooms and cook for about 3-5 minutes until they start to brown. Remove from heat, sprinkle with ½ teaspoon salt, and combine with the roasted squash and spinach mixture. Toss everything gently.
5. Prepare the Ricotta Filling: In a large mixing bowl, whisk together the egg, ricotta cheese, minced garlic, nutmeg, salt, and black pepper until well combined. Refrigerate until ready to assemble.
6. Adjust oven temperature: Lower the oven temperature to 375°F (190°C) for baking the lasagna layers.
7. Assemble the lasagna: Grease a 13 x 9 inch (2.5-3 inch deep) casserole dish. Spread about one-third of the cauliflower cream sauce evenly across the base. Layer one-third of the no-boil lasagna noodles on top to cover the bottom. Spread half of the ricotta mixture over the noodles, followed by half of the vegetable filling. Sprinkle with 1 cup of shredded mozzarella cheese. Repeat the layering with another third of the noodles, the remaining ricotta, the remaining vegetable filling, and another cup of mozzarella cheese. Top with the last noodles layer.
8. Finish assembly and bake: Pour the remaining cauliflower cream sauce over the top noodles. Sprinkle the last cup of mozzarella cheese evenly on top. Cover the dish tightly with foil and bake for 40 minutes. Remove the foil, sprinkle grated asiago cheese on top, and bake uncovered for an additional 15-20 minutes. For a golden crust, broil for the last 2 minutes if desired.
9. Garnish and serve: Remove from oven and garnish with fried sage leaves (optional), fresh parsley, crushed red pepper flakes, and a little cracked black pepper. Serve hot and enjoy your hearty, flavorful lasagna.

Notes

• No-boil noodles allow you to skip pre-cooking and soften during baking, but breaking pieces to fit the pan helps make even layers.
• Fried sage leaves add an optional crispy herb topping that enhances flavor and texture.
• Adjust seasoning to taste, especially salt and pepper, since cheese and vegetables contribute to the overall flavor.
• Adding a splash of extra almond milk to the cream sauce can help achieve your desired consistency.
• Broiling the lasagna at the end creates a nicely browned and bubbly cheese topping.

Keywords: butternut squash lasagna, vegetarian lasagna, mushroom spinach lasagna, healthy lasagna, vegetable lasagna, creamy cauliflower sauce