This is a comforting, creamy lasagna that comes together with a simple, no-cook white sauce and layers of spinach, pesto, potatoes, and melty mozzarella. I keep the flavors bright with basil and a hit of nutmeg in the ricotta mixture, and the assembly is straightforward enough for a weeknight with just a little patience for layering. Vegetarian Lasagna with No-Cook White Sauce is as cozy as it sounds—rich, fresh, and perfectly cheesy without a complicated béchamel.

Why you’ll love this Vegetarian Lasagna with No-Cook White Sauce

There’s something so satisfying about a lasagna that feels indulgent but uses fresh ingredients and minimal fuss. The no-cook white sauce made from ricotta and milk avoids the stovetop roux and results in a lighter, creamier base for the lasagna. Spinach keeps things green and slightly earthy, while pesto and fresh basil introduce bright herbal notes. Thinly sliced steamed potatoes add a tender, comforting layer that works surprisingly well with the cheesy filling. This Vegetarian Lasagna with No-Cook White Sauce is a great crowd-pleaser and reheats beautifully for leftovers.

Ingredients

500g fresh ricotta cheese
220ml fresh milk
2 tablespoon vegetarian Italian-style hard cheese, or Parmesan for non-veggies, grated
1 tablespoon extra-virgin olive oil
⅛ teaspoon grated nutmeg
Sea salt and freshly cracked black pepper, to taste
2 tablespoon extra-virgin olive oil
300g fresh or defrosted spinach leaves
1 medium shallot or red onion, finely minced
8-10 fresh lasagna pasta sheets
1 cup pea pesto
2 mozzarella balls, very well drained, thinly sliced
2 steamed potatoes, peeled and thinly sliced
handful of basil leaves

Before you begin

Make sure the mozzarella is very well drained so the layers don’t become watery. If your spinach is frozen, thaw and squeeze out as much liquid as possible. Steam the potatoes until tender but still sliceable, then cool before slicing thinly. Have an ovenproof dish ready that fits 8–10 lasagna sheets comfortably.

Step-by-step directions

Preheat your oven to 180°C (350°F). Lightly oil your baking dish with a little extra-virgin olive oil to prevent sticking.
Prepare the no-cook white sauce: In a mixing bowl combine 500g fresh ricotta cheese and 220ml fresh milk. Stir until smooth and creamy. Add 2 tablespoon vegetarian Italian-style hard cheese (or Parmesan if you prefer), 1 tablespoon extra-virgin olive oil, ⅛ teaspoon grated nutmeg, and sea salt and freshly cracked black pepper to taste. Mix thoroughly so the cheese, milk, and seasonings are evenly incorporated. Taste and adjust seasoning as needed.
Sauté the aromatics and spinach: Warm 2 tablespoon extra-virgin olive oil in a skillet over medium heat. Add 1 medium shallot or finely minced red onion and cook until softened and translucent, about 3–4 minutes. Add 300g fresh or defrosted spinach leaves to the skillet and cook until wilted and most of the moisture has evaporated, about 3–5 minutes. Season with a pinch of salt and pepper. Remove from heat and set aside to cool slightly.
Prepare the lasagna sheets: If your fresh lasagna pasta sheets require par-boiling or softening, follow the package instructions; many fresh sheets can be used directly. Lay out 8–10 fresh lasagna pasta sheets within easy reach for assembly.
Layer the first base: Spoon a thin layer of the ricotta mixture across the bottom of the oiled baking dish to create a light coating that prevents sticking. Place the first layer of lasagna sheets over the ricotta base, overlapping slightly if needed to cover the dish.
Add fillings in order: Spread about one-third of the ricotta mixture over the first pasta layer. Dollop and gently spread about one-third cup of the pea pesto (divide the 1 cup across the layers), then scatter a portion of the sautéed spinach and a few basil leaves across the pesto. Arrange some thin slices of steamed potato in a single layer and add a few thin slices of mozzarella on top.
Repeat layering: Lay another layer of lasagna sheets over the fillings. Repeat the same sequence—about one-third of the ricotta mixture, another portion of pesto, more spinach, more potato slices, and more mozzarella. Continue until you have used the majority of the components, finishing with a final layer of lasagna sheets.
Top layer: Spread the remaining ricotta mixture over the top pasta sheet. Finish with the remaining pesto in streaks or dollops and arrange the remaining slices of mozzarella and basil leaves across the top for an attractive finish. Season the top lightly with a bit of salt and freshly cracked black pepper.
Bake the lasagna: Cover the dish with foil and bake in the preheated oven for 25 minutes. Remove the foil and bake for an additional 10–15 minutes, or until the cheese is melted, the top is bubbly, and the edges are lightly golden. If you want a more browned top, switch to grill/broil for 1–2 minutes while watching carefully.
Rest and serve: Remove the lasagna from the oven and let it rest for 10–15 minutes before slicing. This resting time helps the layers set so the portions hold together. Garnish with extra basil leaves if you like, then slice and serve warm.

Notes and tips

Ricotta consistency: If your ricotta is very thick, the 220ml fresh milk helps loosen it to a spreadable, silky sauce. Adjust the milk slightly if needed for a smoother texture, but keep the quantities listed for the intended balance.
Spinach moisture: Press out as much water as possible from defrosted spinach to avoid a watery lasagna. Cooked spinach should be seasoned lightly since the ricotta mixture and pesto add salt and flavor.
Pesto variation: Pea pesto adds a bright sweetness and color. If you prefer, use a traditional basil pesto or a store-bought version—just keep the 1 cup amount called for in the recipe.
Lasagna sheets: Fresh pasta sheets are convenient because they generally don’t need pre-cooking. If yours require boiling, follow the package instructions and layer immediately. The recipe calls for 8–10 sheets depending on the size of your dish and how many layers you want.
Make-ahead: Assemble the lasagna up to the point of baking, cover, and refrigerate for up to 24 hours. Add 5–10 extra minutes to the baking time if you bake straight from chilled.
Leftovers: Refrigerate any leftovers in an airtight container for up to 3 days. Reheat in the oven at 160–170°C (325–340°F) until warmed through to preserve texture.

Serving suggestions

Serve this Vegetarian Lasagna with No-Cook White Sauce with a crisp green salad to cut through the richness and a glass of your favorite white wine or sparkling water with lemon. A simple arugula salad with lemon vinaigrette or a cucumber-tomato salad offers a refreshing counterpoint to the creamy layers.

Final thoughts

Vegetarian Lasagna with No-Cook White Sauce brings together creamy ricotta, vibrant pesto, tender potatoes, and fresh spinach in a simple assembly that rewards you with comforting, layered flavor. The no-cook white sauce saves time and produces a delightfully silky texture. Whether you’re feeding a family or making a make-ahead dinner for friends, this lasagna is reliably delicious and satisfying. Enjoy!

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Vegetarian Lasagna with No-Cook White Sauce

A layered vegetarian lasagna featuring a creamy ricotta white sauce, sautéed spinach, pea pesto, potatoes and mozzarella.

Prep Time20

Cook Time25

Total Time45

Servings: 6 servings

Ingredients

500 g fresh ricotta cheese
220 ml fresh milk
2 tablespoons vegetarian Italian-style hard cheese, or Parmesan grated
1 tablespoon extra-virgin olive oil
1/8 teaspoon nutmeg grated
sea salt to taste
freshly cracked black pepper to taste
2 tablespoons extra-virgin olive oil for sautéing
300 g fresh or defrosted spinach leaves
1 medium shallot or red onion finely minced
8-10 fresh lasagna pasta sheets
1 cup pea pesto
2 mozzarella balls very well drained, thinly sliced
2 steamed potatoes peeled and thinly sliced
basil leaves a handful

Instructions

Make the ricotta white sauce: combine ricotta, grated hard cheese, milk and 1 tablespoon olive oil in a blender and blend until smooth and creamy; add a little more milk if needed. Season with sea salt, freshly cracked black pepper and grated nutmeg.
Sauté the spinach: heat 2 tablespoons olive oil in a large skillet over medium-low heat. Add the minced shallot or red onion and the spinach, cover and cook 2 minutes. Uncover, stir and cook another 2 minutes until wilted, then remove from heat.
Preheat the oven to 180°C (350°F) and place a rack in the middle position.
Prepare the baking dish: brush the bottom of a 6x8-inch baking dish with a layer of the ricotta white sauce.
Trim lasagna sheets as needed to fit the dish, then place a layer of sheets over the sauce.
Spread half of the pea pesto evenly over the lasagna sheets, then arrange half of the sliced potatoes, half of the mozzarella slices and half of the basil leaves on top.
Add another layer of lasagna sheets, spread an even layer of ricotta white sauce over them, then top with the sautéed spinach.
Place another layer of lasagna sheets, spread the remaining pea pesto over the pasta, and arrange the remaining sliced potatoes, mozzarella and basil leaves.
Finish with a final layer of lasagna sheets and spread the remaining ricotta white sauce evenly over the top to create a thick white layer.
Bake: place the baking dish in the oven and bake for about 20 minutes, or until the pasta is cooked through and the top is gently bubbling.
If desired, place the lasagna under a preheated grill/broiler for about 5 minutes to develop golden spots on top.
Remove from the oven and let rest briefly before slicing and serving.