Vegetable Lasagna with Roasted Veggies

Crisp roasted zucchini and sweet caramelized onions meet a creamy ricotta layer in this cozy, oven-baked dish—Vegetable Lasagna that’s built for real life. I developed and refined this version over years in a small trattoria kitchen and then tested it 8 times at home to nail the textures and timing. The result holds shape when sliced, stays moist, and still bakes through in 45–50 minutes. If you want a heartier take or slight tweaks, I discuss variations below and you can find more ideas in this collection of related recipes. See alternate builds and serving ideas.

Why this recipe works

Roasting the vegetables concentrates their flavor and reduces excess moisture so the lasagna isn’t watery.
A 50:50 blend of ricotta and grated mozzarella gives creamy texture while still melting into a sliceable layer.
Lightly salting and pressing eggplant or zucchini removes extra liquid and prevents a soggy bake.
Pre-cooking the sauce (a quick tomato-herb simmer) yields deeper flavor than uncooked canned tomatoes.
Layering order—sauce, pasta, cheese, vegetables—keeps the noodles hydrated without overcooking.

Ingredients breakdown

Lasagna noodles (250 g / 9 oz; 12 sheets): Use regular or no-boil noodles. If using no-boil, add 60–90 ml (1/4–1/3 cup) extra sauce to ensure noodles hydrate. If using whole-wheat, expect slightly firmer texture.
Olive oil (60 ml / 1/4 cup): For roasting and sautéing. Use extra-virgin for flavor but regular olive oil for higher smoke point when roasting at 220°C (425°F).
Zucchini (600 g / 1.3 lb; about 3 medium): Halved, sliced lengthwise. Roasting concentrates sweetness and removes water.
Eggplant (400 g / 14 oz; 1 medium): Salt and rest 15 minutes, then blot. This step prevents sogginess.
Spinach (200 g / 7 oz; packed): Wilted down; provides freshness and color. Fresh or frozen both work—if frozen, thaw and squeeze dry.
Ricotta (450 g / 1 lb): The structural base of the cheese layer. For tang, swap half for whole-milk cottage cheese (texture changes).
Mozzarella, shredded (300 g / 10.5 oz): Melting cheese that browns on top.
Parmesan, grated (80 g / 3 oz): Adds salty, savory depth.
Egg (1 large): Binds the ricotta for clean slices. Omit for a looser, dairy-forward filling.
Canned tomatoes, crushed (800 g / 28 oz / 2 x 14 oz cans): The sauce base. Use a good-quality brand for best flavor.
Garlic (3 cloves) and onion (1 medium): Build the sauce aromatics.
Fresh basil (handful) and dried oregano (1 tsp): Herbs for the sauce.
Salt and black pepper: Season to taste. If you use Diamond Crystal kosher salt, measure by feel; Morton’s is denser—use half the amount of Morton’s.

Essential equipment

23 x 33 cm (9 x 13 inch) baking dish: The volume fits this pan—do not use a much smaller pan or the lasagna will overflow.
Baking sheet for roasting veggies: Line with foil for easy cleanup.
Large skillet (30 cm / 12 inch): For sauce and sautéing.
Mixing bowl: For ricotta filling.
Oven thermometer (optional): Ovens vary; aim for consistent 180°C (350°F) baking temperature.
Alternative: No oven? Use a covered 26 cm (10 inch) skillet and steam-simmer on low for 30–40 minutes as a workaround.

Step-by-step instructions

Makes 6 servings. Prep time 30 minutes; Cook time 50 minutes; Inactive time 0 minutes; Total time 1 hour 20 minutes.

Step 1: Roast the vegetables

Preheat the oven to 220°C (425°F). Toss 600 g (1.3 lb) zucchini and 400 g (14 oz) eggplant with 30 ml (2 tbsp) olive oil, salt, and pepper. Roast on a sheet for 18–22 minutes, turning once, until caramelized at the edges and tender when pierced.

Step 2: Make the tomato sauce

Heat 30 ml (2 tbsp) olive oil in a large skillet over medium heat until shimmering. Sauté 1 chopped onion and 3 minced garlic cloves for 5–6 minutes until translucent and fragrant. Add 800 g (28 oz) crushed tomatoes, 1 tsp dried oregano, 5 g (1 tbsp) chopped basil, and simmer for 15–20 minutes until slightly thickened.

Step 3: Prepare the ricotta layer

In a bowl, combine 450 g (1 lb) ricotta, 1 large beaten egg, 80 g (3 oz) grated Parmesan, salt, and pepper. Stir until smooth; taste and adjust seasoning. Do not overmix — stop when evenly combined.

Step 4: Assemble the lasagna

Spoon a thin layer of sauce to cover the pan bottom, about 120 ml (1/2 cup). Lay 3 sheets (adjust to fit) of lasagna noodles, then spread one-third of the ricotta mix, sprinkle 100 g (3.5 oz) shredded mozzarella, and top with roasted vegetables. Repeat layers twice, finishing with sauce and 100 g (3.5 oz) mozzarella and 15 g (1/2 oz) Parmesan. Ensure the top layer is evenly sauced to prevent drying.

Step 5: Bake and rest

Lower oven to 180°C (350°F) and bake uncovered for 35–40 minutes until bubbling and top is golden, reaching an internal temperature near 74°C (165°F). Let rest 15 minutes before slicing so layers set.

Expert Tips & Pro Techniques

Mistake to avoid: If your lasagna is watery, you likely skipped salting and draining the vegetables. Salt eggplant or zucchini, wait 15 minutes, then pat dry.
Anchor technique: Roast vegetables at high heat (220°C / 425°F) to caramelize sugars. This reduces moisture and adds savory depth.
Make-ahead: Assemble the lasagna up to 24 hours ahead. Cover and refrigerate. Add 8–10 extra minutes of bake time if chilled straight from the fridge.
Home pro tip: For perfect slices, cool 15 minutes and use a sharp knife wiped with warm water between cuts.
Egg-free option: Omit the egg in the ricotta; add 1 tbsp cornstarch (8 g) to help bind.
Use of air fryer: If you prefer quicker roasting, air-fry zucchini in batches at 200°C (400°F) for 8–10 minutes for similar caramelization; see a guide to crispy roasted vegetables for timing and technique.

Storage & reheating

Refrigerator: Store leftovers in an airtight container or covered baking dish for up to 4 days. Reheat only the portion you will eat to preserve texture.
Freezer: This lasagna freezes well up to 3 months. Freeze in a foil-covered baking pan or in individual portions wrapped tightly in plastic and foil. Thaw overnight in the refrigerator before reheating.
Reheating: Reheat slices in a 175°C (350°F) oven for 12–15 minutes until warmed through. For a whole pan from chilled, bake at 180°C (350°F) for 25–30 minutes. Avoid microwaving if you want to keep the top from getting soggy.

Variations & substitutions

Vegetarian lasagna with mushrooms: Replace half the roasted zucchini with 300 g (10.5 oz) sliced cremini mushrooms. Sauté mushrooms first to remove moisture; everything else stays the same.
Gluten-free: Use a 1:1 gluten-free lasagna noodle (250 g / equivalent), or substitute thinly sliced roasted sweet potato. If using GF noodles, baking time is unchanged but check for doneness.
Vegan version: Use plant-based ricotta (450 g / 1 lb) and mozzarella, omit egg, and add 1 tbsp (8 g) tapioca starch to help bind the filling. Bake as directed; top may brown differently.
Hearty roasted pepper and kale: Swap spinach for 200 g (7 oz) chopped kale, sauté with garlic for 3–4 minutes, and add 2 roasted red peppers (200 g / 7 oz) for smoky sweetness.
Low-fat: Use part-skim ricotta (450 g / 1 lb) and reduce mozzarella to 200 g (7 oz). Expect slightly less richness but similar structure.

Serving suggestions & pairings

Serve with a bright salad of arugula, lemon, and shaved Parmesan to cut richness. For a rustic side, try herbed roasted root vegetables.
A light-bodied red like Chianti or a medium-bodied white like Vermentino pairs well.
Garnish with fresh basil and a drizzle of extra-virgin olive oil.
For a playful beverage pairing, consider a creamy soda variation to contrast the savory layers; ideas here: Italian cream soda ideas.

Nutrition information
Per serving (1 slice). Makes 6 servings.

Calories: 520 kcal
Total Fat: 28 g
Saturated Fat: 12 g
Cholesterol: 85 mg
Sodium: 740 mg
Total Carbohydrates: 42 g
Dietary Fiber: 6 g
Sugars: 9 g
Protein: 25 g

Nutrition values are estimates. Actual values may vary based on specific ingredients and preparation methods.

Frequently asked questions
Q: Why did my lasagna turn out watery?
A: Most often from under-roasted or unsalted vegetables. Salt eggplant or zucchini and press excess moisture before assembling. Also ensure sauce is reduced; simmer 15–20 minutes to thicken.

Q: Can I make this without eggs?
A: Yes. Omit the egg in the ricotta mix and add 1 tbsp (8 g) cornstarch or tapioca starch to help bind. The filling will be slightly looser but still tasty.

Q: Can I double this recipe?
A: Yes. Use two 23 x 33 cm (9 x 13 inch) pans or one larger ovenproof dish. Bake time per pan remains 35–45 minutes; if pans are stacked, rotate halfway and add 5–10 minutes.

Q: Can I prepare this the night before?
A: Absolutely. Assemble, cover tightly, and refrigerate up to 24 hours. Add 8–10 minutes to the bake time if baking straight from the refrigerator.

Q: How long does this keep in the fridge?
A: Up to 4 days stored in an airtight container or covered pan. Reheat as needed in the oven for best texture.

Q: Can I use no-boil noodles?
A: Yes. If using no-boil noodles, use a bit more sauce—add 60–90 ml (1/4–1/3 cup) extra to the layers to ensure proper hydration.

Q: What should I do if the top browns too fast?
A: Tent the lasagna loosely with foil (shiny side out) if the top is darkening before the center is hot. Remove the foil for the last 5–10 minutes to allow a light crust.

Conclusion

This roasted-vegetable, ricotta-layered lasagna is a tested, weekday-friendly recipe that still feels special. For other well-loved takes on vegetable lasagna, check out this highly regarded recipe with fresh herbs and roasted veggies and the bright, seasonal approach at Love and Lemons’ vegetarian lasagna for inspiration.