Step 1

Preheat oven to 350 degrees F.

Step 2

To make the sauce, melt butter in a saucepan over medium heat. Add garlic, mushrooms and onion. Cook, stirring occasionally, until tender, about 3-4 minutes. Whisk in flour until lightly browned, about 1 minute.

Step 3

Gradually whisk in milk, and cook, whisking constantly, until slightly thickened, about 2-3 minutes. Stir in basil, oregano and nutmeg until fragrant, about 1 minute; season with salt and pepper, to taste; set aside.

Step 4

In a large pot of boiling salted water, cook lasagna noodles according to package instructions.

Step 5

Spread 1 cup mushroom sauce onto the bottom of a 9×13 baking dish; top with 3 lasagna noodles, 1/2 of the ricotta cheese, 1/2 of the spinach, 1 cup mozzarella cheese and 1/4 cup Parmesan. Repeat with a second layer. Top with remaining noodles, mushroom sauce and cheeses.*

Step 6

Place into oven and bake for 35-45 minutes, or until bubbling. Then broil for 2-3 minutes, or until top is browned in spots. Let cool 15 minutes.

Step 7

Serve, garnished with parsley, if desired.