2 tablespoons olive oil
1 large white onion
350 g / 12.5 ounces Arborio rice
300 g Hokkaido pumpkin with skin, or peeled butternut squash
120 ml / ½ cup white wine
1.5 l / 6 cups vegetable or chicken broth
60 g / 2 ounces unsalted butter
120 g / 4 ounces freshly grated Parmesan, plus more for serving
Fine sea salt
Ground black pepper
50 g hazelnuts, skin-on
200 g / 7 ounces chanterelles mushrooms (fresh or frozen and thawed)