The broth should already be boiling on the stove.
Coarsely chop the onion and put it in a pan to sauté with a drizzle of oil.
Peel and cut the pumpkin into medium-large pieces. Add it to the onion and cover with two or three ladles of vegetable broth, so as to cover it completely.
Cover with the lid until cooked through.
In a nonstick skillet, toast the rice for 3-4 minutes in a drizzle of oil until shiny.
Raise the heat and deglaze with the white wine, let it evaporate.
When the pumpkin is so soft that it breaks up when you turn it with a spoon, add the rice to the pumpkin and cover with abundant vegetable broth, add salt and let it cook slowly.
When the broth has been absorbed, taste to understand the level of cooking and, if necessary, add more broth, until the risotto has reached the consistency you prefer.
When the risotto is cooked, turn off the heat, add a knob of butter and the grated Parmesan cheese.
Stir constantly for a couple of minutes and, if you like, add some black pepper. Grated nutmeg, chopped rosemary or some crispy bacon are also great finish touches!