I made this the other night and it was soooo good. A very different take on lasagna but this is actually my very first successful making of any type of lasagna. You also learn how to make a white sauce here which most people think they have to buy. I got the recipe here.
*Note: If you don't care to use no-boil noodles or don't have them on hand, substitute regular lasagna noodles, boiling and draining them prior to assembling the lasagna.
12 no-boil lasagna noodles (I prefer the Barilla brand)
1 large clove garlic, minced
4 cups whole milk
3/4 cup (12 tablespoons or 1 1/2 sticks) butter, divided
1/2 cup all-purpose flour
1 teaspoon freshly ground black pepper
1/4 teaspoon ground nutmeg
1 1/2 pounds cremini or baby bella mushrooms (or a combination of both)
1 1/2 cups freshly grated Parmesan or Parmigiano-Reggiano cheese
Preheat the oven to 375°F.
For the white sauce, bring the milk and garlic to a simmer in a medium saucepan, or heat it in your microwave in a glass liquid measure, and set it aside. In a large saucepan, melt 1/2 cup (8 tablespoons or 1 stick) butter. Add the flour and cook for one minute over low heat, stirring constantly with a whisk or wooden spoon. Pour in the hot milk, a little at a time at first and whisking until combined. Once you’ve added half of it, you can add the second half all at once, along with 1 1/2 teaspoons table salt, the pepper, and nutmeg. Cook the white sauce over medium-low heat, stirring or whisking frequently, anywhere from 3 to 10 minutes, or until thick. Set aside.
To prepare the mushrooms, slice the mushrooms 1/4-inch thick, trimming stems if desired (I left them on). In a large 12-inch skillet, heat 2 tablespoons olive oil and 2 tablespoons butter over medium heat. Add the mushrooms with a couple pinches of salt and cook for about 5 minutes, until they are tender and release some of their juices. Stir occasionally to make sure they cook evenly.
To assemble the lasagna, lightly coat with cooking spray the bottom and sides of a 9X13-inch baking dish. Spread 1/4 cup or so of the white sauce in the bottom of the dish. Arrange a layer of noodles on top (I used 3 no-boil noodles for each layer without overlapping them - just laying them next to each other), then more sauce (about 1/4 of what remains), 1/3 of the mushrooms and 1/3 or so cup of the grated cheese. Repeat two more times then top with a final layer of noodles, your remaining sauce and last 1/4 cup of cheese.
Bake the lasagna for 45 minutes, or until top is browned and the sauce is bubbly. Remove from oven and let sit, lightly covered for 10-15 minutes before serving.