Steam the garlic and onions until translucent. Dice butternut squash and add, season with pepper and sugar. When the cubes are still firm, pour in the white wine and vegetable stock. Continue simmering until the pumpkin is firm to the bite. Add thyme, nutmeg, salt and crème fraîche, bring to the boil and thicken. Stir in the parmesan, season to taste. You can also crush a few pumpkin cubes to make the sauce smoother.
Arrange the pasta on plates and pour the pumpkin sauce over them.