In a large saucepan or braiser, sauté the garlic in olive oil, along with the peperoncino (if using), until the garlic has just browned. Remove the garlic (and peperoncino) and add the squash. Season with salt and pepper and mix everything well. Lower the heat as far as it will go, cover the pan, and allow the squash to braise gently until it is quite soft and beginning to 'melt' into a kind of cream. Add a few drops of water if things get too dry; the squash should not brown. (NB: If using red pepper flakes instead of the peperoncino, add a pinch at the end of this step.)

Add enough water to the pan to cover the squash by at least a good 3 cm/1 inch. Bring to a brisk boil and add the pasta. Mix and let the pasta simmer until it is cooked al dente and has absorbed most of the water. (Add more water if the dish dries out before the pasta is cooked.) You can serve the dish rather soupy or wait until the water is almost completely absorbed. If you like, mix in some finely chopped parsley just a few minutes before serving.

Serve immediately, topped with grated cheese or not, as you prefer.