Cut the pumpkin into cubes and cook in a pan with a little water. Once ready, blend it leaving a few pieces aside.
In a saucepan sauté the onion with a little oil: pour the rice and toast, then simmer with white wine.
Bring the rice to the boil, adding the vegetable stock from time to time with a ladle. At the end of cooking add the porcini mushrooms, previously cooked with a few bay leaves and the pumpkin cubes kept aside.
Mix everything well, turn off the heat and stir with butter, parmesan and pumpkin puree. Serve when it’s still hot.