PENNE WITH BUTTERNUT-SAGE SAUCE

Penne with Butternut-Sage Sauce image

Yield Makes 4 to 6 servings

Number Of Ingredients 9

1 lb peeled butternut squash pieces
1 small onion, quartered
1/2 stick (1/4 cup) unsalted butter
1 tablespoon finely chopped fresh sage
1 1/2 cups water
3/4 teaspoon salt
1/2 teaspoon black pepper
2 oz finely grated Parmigiano-Reggiano (1 cup) plus additional for serving
1 lb penne rigate

Steps:

Process squash and onion in a food processor until finely chopped, about 1 minute.
Heat butter in a 5- to 6-quart heavy pot over moderately high heat until foam subsides, then add sage and cook until fragrant, about 15 seconds. Add chopped squash mixture, water, salt, and pepper and simmer, uncovered, stirring occasionally, until water is evaporated and squash is very tender, 8 to 10 minutes. Stir in Parmigiano-Reggiano and remove squash mixture from heat.
While squash mixture simmers, cook penne in a 6- to 8-quart pot of boiling salted water until al dente. Reserve 1 cup pasta cooking water, then drain pasta in a colander. Add 1/2 cup cooking water to squash mixture, then add drained pasta, tossing to combine.
Thin sauce with additional cooking water as desired and serve pasta with additional cheese on the side.