Because preparing fresh squash can be time-consuming, we used frozen squash as a shortcut here. You can substitute an equal amount of puréed fresh squash (see note below).
Recipe information
Yield
serves 6
Ingredients
Preparation
Step 1
Preheat the oven to 400°F. Butter a 9-by-13-inch baking dish. Heat 3 tablespoons of the oil in a large skillet over medium-low heat. Add the onions; season with salt and pepper. Cover; cook until the onions are soft and release their liquid, about 15 minutes. Uncover; raise the heat to medium. Cook, stirring, until the onions are browned, 20 to 25 minutes. Stir in 1 teaspoon of the rosemary.
Step 2
Meanwhile, cook the pasta in a large pot of boiling salted water for 2 minutes less than the package instructions suggest. Drain, reserving 1 1/2 cups of the cooking water. Return the pasta to the pot.
Step 3
Stir squash and reserved pasta water into the onions; simmer for 2 minutes. Toss the squash mixture and 1/2 cup of the Parmesan with the pasta. Transfer to the prepared dish.
Step 4
Combine the bread cubes with the remaining Parmesan, rosemary, and oil; season with salt and pepper. Top the pasta with the bread cubes; bake until golden brown, 10 to 15 minutes.
Substituting Fresh Squash
Step 5
Roast whole winter squash on a rimmed baking sheet, turning occasionally, until very tender when pierced with a knife, about 1 hour, depending on the size of the squash. When cool enough to handle, halve the squash lengthwise and scrape the flesh into a food processor (discard the skin and seeds). Purée until smooth. You will need 2 cups (from about 3/4 pound squash).
