PREPARATION:
Preheat the oven to 350 degrees. Cut the squash in half, splitting it down the middle. Scoop the seeds and stringy filling out of the cavity. Rub the squash all over with olive oil. Then, wrap the squash in aluminum foil. Lay the squash flat-side down on a sheet and bake for 30-40 minutes — until the flesh softens and can be spooned out.
About 20 minutes, heat olive oil in a skill. Add in the diced onion, stirring constantly. When the onion turns translucent, turn off the heat. Take the squash out of the oven and let them cool, unwrapped, for 2-3 min. Scoop out the squash pulp and mix it in the pan with the onion. Meanwhile, cook the pasta al dente.
Stir squash and parmigiano until a creamy mix has formed. The cheese will melt, blending into the softened pulp. Season to taste with fresh ground black pepper. As a final step, toss the cooked pasta in the cheese-and-squash mix.
To ensure an even coating, add a little hot pasta water to the skillet while stirring. Pour the water in 1 tablespoon at a time to avoid a runny sauce. Shake the pan once or twice to ensure equal distribution of the sauce. Serve it hot, sprinkled with a spoonful of grated cheese or fried sage.
Buon appetito!