12 lasagna noodles

2 tablespoons olive oil

1 medium onion, chopped

3 cloves garlic, minced

2 cups mushrooms, sliced (cremini or button recommended)

4 cups fresh spinach, chopped

1 teaspoon dried oregano

1 teaspoon dried basil

1/4 teaspoon ground nutmeg

2 cups ricotta cheese

2 cups shredded mozzarella cheese

1/2 cup grated Parmesan cheese

4 cups milk

4 tablespoons butter

1/4 cup all-purpose flour

Salt and pepper, to taste

Preheat oven to 375°F (190°C).
Cook lasagna noodles according to package instructions. Drain and set aside.
In a large skillet, heat olive oil over medium heat. Sauté onion and garlic for 2–3 minutes.
Add mushrooms; cook 5–7 minutes until tender and moisture is released.
Stir in spinach; cook for 2 minutes until wilted. Season with oregano, basil, nutmeg, salt, and pepper. Remove from heat.
In a saucepan, melt butter. Whisk in flour to create a roux; cook 1 minute.
Gradually whisk in milk. Simmer and stir until thickened (about 5 minutes). Season with salt and pepper.
In a 9×13-inch baking dish, spread a thin layer of béchamel.
Layer noodles, mushroom-spinach mixture, dollops of ricotta, and sprinkle with mozzarella and Parmesan.
Repeat layers, ending with béchamel and cheeses on top.
Cover with foil; bake 25 minutes. Uncover and bake another 10 minutes until bubbly and golden.
Let rest 10 minutes before serving.

Use kale instead of spinach for a heartier version.

For a richer taste, swap mozzarella with Gruyère or fontina.

Make it vegan with dairy-free milk, vegan cheese, and olive oil in place of butter.

Add roasted red peppers or sun-dried tomatoes for extra flavor.

Add white beans or lentils for added protein.

Leftovers keep for 4 days in the fridge or 3 months in the freezer.