1. Remove pumpkin skin. Cut pumpkin into small pieces and boil until soft.
2. Puree the pumpkin with vegetable stock and a little water. This sauce is much better thick than watery, so it is better to add water later then puree the pumpkin with too much water.
3. Fry mushrooms with garlic and oil/ vegan butter. When the mushrooms are cooked, add to pureed pumpkin and let the sauce simmer for a few minutes, then pour over your favorite pasta.