Sweet Potato Squash Lasagna

A cozy, crowd-pleasing Sweet Potato Squash Lasagna layered with roasted root vegetables, creamy ricotta, and melted mozzarella. Perfect for vegetarian comfort food lovers.

Why This Recipe Works:

• High-Heat Roasting: Roasting the sweet potatoes, squash, and carrots at 400°F dehydrates the vegetables, preventing a watery lasagna while concentrating their natural sugars.
• Starch Gelatinization: The natural starches in the sweet potatoes help bind the layers together as the lasagna cools, ensuring clean, perfect slices.
• Acid Balance: A splash of fresh lemon juice in the ricotta mixture cuts through the heavy sweetness of the root vegetables, keeping the flavor profile bright and balanced.

Three years ago, I spent an entire Saturday scraping stubborn orange puree off my kitchen ceiling after my cheap food processor lid flew off mid-whiz.

My sister had requested a meatless birthday dinner, and I, full of unearned confidence, promised a show-stopping vegetable lasagna that would make even the most dedicated carnivores at the table forget about beef.

But here is the cold, hard truth about baking sweet potatoes, butternut squash, and carrots together in a casserole: they are packed with water that releases during baking, turning your beautiful layers into a swampy, structural nightmare where the noodles slide right off the plate.

I tried using a cheap plastic mandoline to slice them, but it failed every test because the blade flexed under the dense sweet potatoes, which got annoying fast.

Think about this in terms of physics.

To fix this, we must roast our sliced root vegetables at high heat before they ever touch a noodle, which coaxes out the water and triggers the Maillard reaction for a deep, caramelized sweetness.

Trust me on this one, this method is hands down the easiest way to get clean, stackable slices of veggie heaven without any fancy equipment.

If you love these cozy Italian flavors but want something that comes together in half the time, you might also enjoy our Lasagna Tortellini Soup for a quick weeknight fix.

Sweet Potato Squash Lasagna

• Publisher Storied Skillet
• Cuisine Italian-American
• Category Dinner, Vegetarian
• Prep Time 30 mins
• Cook Time 1 hour 15 mins
• Servings 8 servings
• Calories 380 calories
• Rating 4.8 4972
• Tags sweet potato lasagna, butternut squash lasagna, veggie lasagna, vegetarian comfort food

Ingredients

• 2 medium sweet potatoes, peeled and sliced thin (1/8-inch)
• 1 small butternut squash, neck only, peeled and sliced thin (1/8-inch)
• 3 large carrots, peeled and sliced thin lengthwise
• 2 tbsp olive oil
• 1.5 tsp Diamond Crystal kosher salt, divided
• 0.5 tsp freshly cracked black pepper
• 15 oz whole milk ricotta cheese
• 1 large egg
• 0.5 cup grated Parmesan cheese, divided
• 2 cups shredded mozzarella cheese, divided
• 2 cloves garlic, minced
• 1 tbsp fresh thyme leaves
• 12 no-boil lasagna noodles
• 3 cups marinara sauce

Directions

1. Preheat oven to 400°F (200°C). Toss the sliced sweet potatoes, butternut squash, and carrots with olive oil, 1 teaspoon of Diamond Crystal kosher salt, and black pepper.
2. Arrange the vegetables in a single layer on two large baking sheets. Roast for 20 minutes until tender and slightly caramelized at the edges. Remove from oven and let cool slightly.
3. In a medium bowl, combine the ricotta cheese, egg, minced garlic, fresh thyme, half of the Parmesan, and the remaining 0.5 teaspoon of salt. Stir until smooth.
4. Reduce oven temperature to 375°F (190°C). Spread 1/2 cup of marinara sauce over the bottom of a 9x13-inch baking dish.
5. Place 3 lasagna noodles over the sauce. Layer a third of the roasted vegetables, spread a third of the ricotta mixture, and sprinkle with 1/2 cup of mozzarella. Repeat layers twice more.
6. Top with the final 3 noodles, remaining marinara sauce, remaining mozzarella, and remaining Parmesan cheese.
7. Cover tightly with foil and bake for 40 minutes. Remove foil and bake for an additional 15 minutes until the cheese is bubbly and golden brown.
8. Let the lasagna rest for 15 minutes before slicing to allow the layers to set.

Notes

• Salt Conversion: Always use Diamond Crystal kosher salt for even seasoning. If you only have standard table salt, cut the measurement in half (use 3/4 tsp total instead of 1.5 tsp) to avoid an oversalted dish.
• The Egg Binder Science: Do not skip the egg in the ricotta mixture. The egg proteins coagulate during baking, creating a strong protein matrix that traps the moisture from the cheese and vegetables, preventing the lasagna from collapsing when sliced.
• Slicing Thickness: For the best texture, use a mandoline to slice the sweet potatoes and butternut squash. Slices thicker than 1/8-inch will take much longer to roast and won't layer as elegantly.
• Burn Prevention: Keep a close eye on the oven during the final 15 minutes of uncovered baking. If the mozzarella starts to brown too quickly before the noodles are tender, loosely tent the dish with foil to protect the cheese.
• Make-Ahead Magic: This lasagna is a prime candidate for meal prep. The starches in the sweet potatoes fully gelatinize as they cool, meaning it actually slices cleaner and tastes deeper after a night in the fridge.

Serving Suggestions

This rich, comforting lasagna pairs beautifully with bright, fresh sides that cut through the sweet and savory layers of roasted root vegetables.

• A crisp green salad tossed with a zesty lemon vinaigrette.
• Warm, crusty garlic bread for scraping up every last bit of marinara.
• Roasted broccoli or asparagus spears tossed with lemon zest and red pepper flakes.
• A light, dry red wine like Chianti or Pinot Noir to complement the tomato sauce.

Storage and Reheating

Let's be honest: lasagna is always better the next day.

Store any leftovers in an airtight container in the refrigerator for up to four days. The cool environment allows the sweet potato starches to fully lock in, making your reheated slices incredibly sturdy and neat.

When you are ready to reheat, skip the microwave if you want to preserve the texture of the roasted vegetables. Instead, place a slice in an oven-safe dish, splash a tablespoon of water or extra marinara over the top to keep it moist, cover it tightly with foil, and bake at 350°F for about 20 minutes until heated through.

For freezing, wrap individual baked slices tightly in plastic wrap and then foil for up to three months. Thaw in the fridge overnight before reheating.

Ingredient Substitutes

If you don't have all these exact root vegetables on hand, don't panic. Lasagna is highly adaptable, and you can easily swap ingredients based on what's in your crisper drawer.

1. Butternut Squash: Swap with pumpkin or extra sweet potatoes. If you want a completely different low-carb vibe, try using zucchini slices like we do in our Umami Zucchini Noodles.
2. Marinara Sauce: You can use a rich meat sauce instead. If you want a comforting, creamy alternative, try layering the vegetables with a white sauce similar to the one in our Turkey Spinach Veggie Lasagna.
3. Sweet Potatoes: If you want to skip the sweet potatoes entirely, you can substitute them with roasted gold potatoes or even roasted butternut squash. For another cozy sweet potato idea, check out our Sweet Potato Leek Soup.
4. Ricotta Cheese: Cottage cheese makes an excellent high-protein substitute. Just blend it first to get a silky texture that mimics ricotta perfectly.

Gather your family, pull up a chair, and enjoy a big, warm slice of this cozy vegetable bake. It is proof that comfort food doesn't need meat to feel like a giant hug.