1 medium butternut squash, about 1 1/2-2 pounds or about 4-5 cups cooked
1 tablespoon olive oil, plus some oil for brushing the squash before roasting
1 tablespoon butter
1 large shallot, thinly sliced
1 cup whole milk or half n' half
2 tablespoons fresh chopped sage, or more if you really like sage
1/2 cup freshly grated Parmigiano-Reggiano cheese, plus extra for garnish
1/4 teaspoon crushed red pepper flakes
1/4 teaspoons salt
8 ounces fettucine or other thick pasta noodles
1. Preheat the oven to 400 degrees F. Line a large, rimmed baking sheet with aluminum foil for easy clean up. Slice the squash in half and scoop out the seeds and discard. Brush the flesh with a little olive oil. Roast for 35-45 minutes or until tender when pierced with a fork. Let cool for 10 minutes before scooping out the flesh. Discard the skins. Mash and stir the squash with a spoon.
2. In a large pot over medium heat, warm 1 tablespoon olive oil and butter. Add the shallot and saute about 5 minutes until browned and softened. Add the cooked squash and milk and stir well. Bring to a slight boil. Then lower the heat and add remaining ingredients through salt. Cook, stirring occasionally, about 8-10 minutes, until sauce thickens.
3. Cook pasta in salted water until al dente or firm. Drain the pasta, reserving a cup or so of the hot pasta water. Add the pasta to the squash mixture, stirring until well coated. In small increments, add hot pasta water to thin the sauce, until desired consistency is reached. Heat through about 2-3 minutes. Taste it and adjust seasonings as desired. Transfer to a serving platter and sprinkle with grated cheese. Serve hot.