-
1
Place a large Dutch oven over medium-high heat.
-
2
Add the olive oil and 2 tablespoons of the butter to the pan.
-
3
Once the butter melts and starts to foam, add the diced onions to the pan and saute until translucent, about 3 to 4 minutes.
-
4
Add the garlic to the pan and cook until fragrant, about 30 seconds.
-
5
Add the mushrooms, thyme, and marjoram and cook, stirring often, until they have released their liquid and caramelized, about 12 to 15 minutes.
-
6
Add 1 tablespoon of the flour and stir to combine.
-
7
Add the wine and cook until mostly reduced.
-
8
Add the chopped tomatoes, tomato paste, stock, 1/4 cup of the heavy cream, 1 1/2 teaspoons of salt and 1/4 teaspoon black pepper and cook, stirring occasionally, until the liquid has reduced and the sauce is thick enough to coat the back of a spoon, about 10 to 15 minutes.
-
9
Taste and adjust seasoning, if necessary.
-
10
Add the parsley to the pan, stir to incorporate and reserve while you prepare the bechamel.
-
11
Preheat the oven to 350 degrees F.
-
12
In a large saucepan heat 6 tablespoons of the remaining butter until melted.
-
13
Add the remaining 6 tablespoons of flour and whisk to combine.
-
14
Cook, stirring for 2 to 3 minutes; do not allow to color.
-
15
Slowly whisk in the milk and increase the heat to medium-high heat.
-
16
Cook, whisking constantly, until mixture comes to a boil and thickens, 4 to 6 minutes.
-
17
Season with the remaining 3/4 teaspoon salt, pinch of white pepper, and the nutmeg.
-
18
Whisk in 1 cup of the Pecorino Romano, cover, and set aside.
-
19
Using the remaining tablespoon of butter, grease a 10 by 15-inch (3-inches deep) baking dish or lasagna pan.
-
20
Spoon 1/4 of the mushroom sauce onto the bottom of the dish.
-
21
Cover with a single layer of no-boil lasagna pasta.
-
22
Top the pasta with another 1/4 of mushroom sauce, then 1/3 of the bechamel sauce.
-
23
Repeat the layering with more pasta, mushroom sauce, and bechamel, until all of the ingredients are used up.
-
24
The top layer should be bechamel sauce.
-
25
Sprinkle the top with the mozzarella cheese and the remaining pecorino.
-
26
Drizzle the remaining 1/2 cup of heavy cream over the top, cover tightly with aluminum foil, and bake the lasagna, undisturbed, for 1 hour.
-
27
Uncover the lasagna and continue baking until the lasagna is puffed, golden brown on top and a paring knife inserted into the lasagna meets with no resistance, about 20 minutes longer.
-
28
Let the lasagna rest for 15 minutes before serving.
-
29
Garnish with chopped fresh herbs.
