Winter Lasagna With Mushrooms, Spinach, and Tarragon

Posted per request

• Ready In: 1 hr 55 mins
• Serves: 8

Ingredients

• Mushroom Ragu

• 2  tablespoons unsalted butter
• 1 1⁄2 lbs white button mushrooms or 1 1⁄2 lbs cremini mushrooms, cleaned and thinly sliced
• 1 (16 ounce) package frozen chopped spinach, thawed and squeezed dry
• 4  teaspoons  minced  fresh tarragon leaves
• 1⁄2 teaspoon  grated nutmeg

• White Wine Veloute

• 8  tablespoons unsalted butter, cut into small pieces
• 1  large onion, minced
• 6  tablespoons all-purpose flour
• 2  cups chicken broth
• 2  cups  whole milk (do not use fat free) or 2  cups low-fat milk (do not use fat free)
• 1  cup white wine (preferably a smooth white Burgundy or a fruity Pinot Gris)

• Casserole

• 9  no-boil lasagna noodles
• 12  ounces  emmenthaler cheese or 12  ounces gruyere, grated

Directions

1. Make mushroom ragu: melt 2 tablespoons butter in a big skillet over medium heat; add in mushrooms; saute for 4 minutes, until they give off their liquid and it reduces to a glaze.
2. Stir in the chopped spinach, tarragon, and nutmeg; cook/stir for 1 minute; remove from heat, cover, and set aside.
3. Make white wine veloute: put cut up 8 tablespoons butter and onion in a large, cool saucepan; set over medium-low heat; as the butter melts, stir often so that the onion is coated.
4. Decrease heat to low and cook until the onion is very soft, almost caramelized, and golden, stirring often, about 12 minutes.
5. Cover and decrease heat even further, and cook for another 5 minutes, stirring once or twice.
6. Meanwhile, position the oven rack in the center of the oven; preheat to 400°.
7. Take the lid off the pan and sprinkle with flour evenly over the onion.
8. Whisking constantly, cook just so the flour loses its raw taste and forms a paste with the liquid in the pan, about 20 seconds (do not brown).
9. Whisk in the broth and milk in a slow, steady stream; increase heat to medium-low and continue cooking, whisking constantly, until the sauce starts to bubble and gets noticeably thicker, about 2 minutes.
10. Whisk in the wine and continue simmering, whisking all the while, until thickened like a heavy cream sauce, about 2 minutes.
11. Set the pan aside off the heat and give the mixture one more good whisking.
12. Layer the casserole in a 13x9 inch baking dish as follows: ½ cup white wine veloute, spread across the bottom of the dish; 3 no-boil noodles, 2 cups white wine veloute, spread over the noodles with a rubber spatula; half the mushroom ragu, spread gently over the casserole, 1/3 of the grated cheese, 3 no-boil noodles, 2 cups white wine veloute; the remaining mushroom ragus; half the remaining cheese, the remaining noodles, the rest of the white wine veloute; and finally the rest of the grated cheese.
13. Bake, uncovered, until bubbly and set, about 40 minutes.
14. Let stand at room temperature for 5-10 minutes before serving.