4 cheese lasagna with mushrooms, squash and leeks

Ingredients

• 8 tablespoons (1 stick) unsalted butter
• 1 pound portabella mushrooms, thinly sliced
• 1 cup finely chopped yellow onion
• 3 tablespoons minced garlic
• 1/2 cup all-purpose flour
• 7 cups milk
• 2 teaspoons kosher salt
• 1/2 teaspoon freshly ground black pepper
• 1/4 teaspoon freshly grated nutmeg
• 1 pound spinach, stemmed, washed, blanched and roughly chopped
• 1 pound shitake mushrooms thinly sliced
• 1 pound cubed butternut squash
• 1 pound thinly sliced leeks
  
• 2 cups grated Parmesan
• 8 ounces goat cheese
• 8 ounces fontina
  
• 8 ounces mozzarella
• 8 ounces gouda
  
• 2 tablespoons olive oil, plus more for coating casserole dish
• 1 pound no boil lasagna sheets
• 1 tablespoon butter, cut into 8 pieces

Directions

Preheat oven to 450. roast leeks, shitakes, and squash with salt, pepper, and olive oil 30-45 minutes until tender. Turn oven down to 375. Set aside.
Melt the butter in a large saucepan over medium heat. Add the mushrooms and cook, stirring often until the mushrooms are browned and most of the liquid has evaporated, about 5 to 7 minutes. Add the onions and garlic to the pan and saute until soft and translucent, 3 to 4 minutes. Add the flour and cook, stirring with a wooden spoon, to make a light roux, about 2 minutes. Whisking constantly, slowly add the milk and continue to cook, stirring occasionally until thickened, 5 minutes. Add 1 1/2 teaspoons of the salt, pepper, nutmeg, spinach and 1 1/2 cups of the Parmesan and cook, stirring, until thickened, about 2 minutes. Remove from the heat. Place a piece of plastic wrap directly on the surface of the bechamel sauce until ready to assemble the lasagna.

Preheat the oven to 375 degrees F.

Coat a 9 by 13 by 3-inch casserole with olive oil, and spread about 1/2 cup of the bechamel sauce on the bottom of the dish. Lay 3 sheets of pasta across the bottom of the dish and spread 3/4 cup of the bechamel sauce over the pasta. Sprinkle 1/4 of the roasted veggies over the bechamel sauce, then cover with cheeses. Lay another 3 sheets of pasta over.. Repeat 2 additional times with the remaining bechamel sauce, veggies, cheeses, and pasta, ending with a layer of pasta covered with bechamel sauce. Sprinkle the remaining 1/2 cup of Parmesan over the bechamel sauce and scatter the butter pieces over the top. Place the casserole on a parchment paper-lined baking sheet and bake, uncovered, until bubbly and well browned, about 45 minutes. Remove from the oven and allow to cool for at least 20 minutes before serving.

Note: You may need slightly less than the entire package of lasagna noodles, depending on the pan used for the casserole. Also, you may be able to fit more than 3 pieces of pasta in each layer, depending. The pasta can be broken into smaller pieces to fill in the gaps.