Butternut Squash Pasta Sauce

1. Preheat oven to 375F. Using a large, sharp knife, trim ends of squash; halve squash crosswise to separate the bulb from the neck. Peel with a vegetable peeler. Cut both pieces in half lengthwise. With a spoon, scoop out seeds; discard.
2. Cut squash into 2-inch chunks; transfer to a small rimmed baking sheet. Toss with oil and sage; season generously with salt and pepper. Scatter garlic around the squash. Roast until squash is very tender, about 40 minutes, tossing once halfway through. Remove and discard skin from the garlic.
3. Transfer squash and garlic to a food processor; puree. With the motor running, add half-and-half through the feed tube; process until smooth. Add 1 to 2 cups water; continue to process until smooth, adding water to thin if necessary. Season again generously with salt.
4. Cook pasta according to package instructions. Reserve 1 cup pasta water; drain pasta and return to the pot. Pour sauce over the pasta; toss to coat. Add some pasta water to thin the sauce if necessary. Serve with desired toppings.