For the risotto:
1 tablespoon butter or oil
1 cup onion, finely chopped
½ cup white wine
8 cups vegetable broth
2 cups Arborio or Carnaroli rice
freshly grated ricotta salata* or Parmesan cheese
Bring broth to a simmer in a saucepan and simmer, covered. When broth is warm, melt the butter in a 4-quart heavy bottomed pot over medium heat and sauté the onions until translucent. Add rice and cook until fragrant. Stir in the wine until it is absorbed. Stir 1/2 cup warm broth and cook at a strong simmer, stirring frequently, until broth is absorbed. Continue adding broth a little at a time, stirring constantly and letting each addition be absorbed before adding the next, do this until rice is creamy-looking but still al dente (it should be the consistency of thick soup), taste for seasonings as you go. Stir in the squash puree and taste for seasonings, about 1 minute. Finish with cheese and a little butter.
Garnish with crispy fried speck** or prosciutto ribbons.
* ricotta salata is ricotta cheese that has been salted, dried and pressed and has a mild nutty, milky flavor.
**speck is cured pork similar to prosciutto. It is cured for weeks in spices and salt, after which it is delicately smoked and then matured for five months.