SAUSAGE AND MUSHROOM PENNE GRATIN

Sausage and Mushroom Penne Gratin image

Provided by Lillian Chou

Yield Makes 4 to 6 servings

Number Of Ingredients 8

1 pound dried penne
1 pound bulk sweet Italian sausage
2 tablespoons olive oil, divided
1 pound packaged sliced mushrooms
1 garlic clove, forced through a garlic press
1 cup heavy cream
1/2 cup grated Parmigiano-Reggiano
8 ounces shredded whole-milk mozzarella, divided

Steps:

Cook penne in a pasta pot of boiling salted water (2 tablespoons salt for 6 quarts water) until al dente. Reserve 1/2 cup pasta-cooking water, then drain pasta and transfer to a flameproof 3-quart baking dish.
Preheat broiler.
Meanwhile, cook sausage in 1 tablespoon oil in a 12-inch nonstick skillet over high heat, stirring occasionally and breaking up any large pieces, until no longer pink. Transfer with a slotted spoon to a bowl, leaving fat in skillet.
Add remaining tablespoon oil to skillet along with mushrooms and garlic, then cook over high heat, stirring occasionally, until mushrooms are golden, about 3 minutes.
Return sausage to skillet along with cream, reserved 1/2 cup cooking water, a rounded 1/4 teaspoon salt, and 1/4 teaspoon pepper and boil over high heat, stirring once or twice, until thickened, about 4 minutes. Pour over pasta, then stir in Parmigiano-Reggiano, 1/2 cup mozzarella, and salt to taste. Spread evenly in baking dish and top with remaining mozzarella.
Broil 3 to 4 inches from heat until golden brown in spots, about 5 minutes.