Directions
Preheat oven to 400 degrees F. Halve squash lengthwise and seed using a grapefruit knife. In a 13x9 roasting pan, fill with water about 3/4" up the sides and place squash halves facing down so that the skin side is facing up. Bake in the middle of the oven until fork-tender, about 30 minutes. Scrape flesh from squash and puree in a food processor until smooth. Discard skin. Set aside 1 1/2 C of puree and save any remainder for another use (can be made ahead and/or stored in fridge 2-3 days).
While squash is cooking, bring broth to a simmer; turn off heat and keep covered and warm until ready. Cook onion in 2T olive oil or fat in a large skillet (preferably 12" or larger) over medium heat, stirring, until softened, about 5 minutes, being careful not to burn. Add rice, garlic, spices and cook, stirring, 3 minutes. Deglaze with wine and bring back to simmer.
Stir in a ladle of warmed broth and cook at a strong simmer, stirring frequently, until broth is absorbed. Continue simmering, stirring constantly, adding a little more broth each time, until rice is creamy-looking but tastes al dente (about the consistency of thick soup), for a total time just under 20 minutes.
Stir in squash puree, 2 T butter or olive oil, cheese, rosemary and sea salt, and simmer, stirring, 1 minute. (If necessary, thin risotto with some leftover broth.) Add a couple pinches of white pepper, to taste. Serve risotto immediately, garnished with rosemary salt, rosemary sprigs, a drizzle of olive oil and additional grated Parmesan.
Garnish tips: Mound risotto in the center of a serving dish and place three 1" tops of rosemary sprigs bunched together and in the center and top with 2 pinches of course rosemary sea salt, a drizzle of olive oil and some grated Parmesan. Surround with greenery such as curly kale,
kale chips, or rosemary sprigs.