Add the leek and sauté until softened, about 10 minutes. Add the squash, chestnuts, sage, cheesecloth pouch, and water. The water should cover the squash by about 2 inches. Bring to a boil ...

Mix together, check seasoning and spoon back into the squash shells. Scatter over the remaining cheese and bake in the oven for 15 minutes. Finely grate the remaining chestnuts over the cooked ...

Gently fry the onion and squash for 5 minutes ... Remove from the heat and add the chestnuts, walnuts and reserved mushrooms, stirring well. Add the chilli flakes, if using.