Butternut Squash Risotto with Pistachios and Lemon

from Melissa Clark's "Cook This Now: 120 Easy and Delectable Dishes You Can't Wait to Make"

1/2 pound peeled butternut squash
about 6 cups vegetable stock
3 tablespoons unsalted butter or olive oil
1 medium leek, thinly sliced
1 garlic clove, finely chopped
2 cups arborio rice
2 rosemary branches
3/4 teaspoon kosher salt, plus more to taste
1/3 cup dry white wine
finely grated zest of 1 lemon
1/2 teaspoon freshly squeezed lemon juice, plus more to taste
freshly ground black pepper to taste
1/4 cup chopped salted pistachios
grated Parmesan cheese

In a food processor fitted with a fine grating attachment, shred the squash.

In a small saucepan, bring the stock to a simmer. Melt the butter in large skillet over medium heat. Add the leeks and cook, stirring them occasionally, until they are soft, about 5 to 7 minutes. Stir in the garlic and cook it until fragrant, about 1 minute. Add the rice, squash, rosermary, and salt. Stir until most of the grains of rice appear semi-translucent, 3 to 4 minutes. This means they have absorbed some of he fat from the pan, which will help keep the grains separate from each other as they form their creamy sauce.

Pour the wine into the pan and let it cook off for about 2 minutes. Add a ladleful of stock (about 1/2 cup) and cook, stirring it constantly and making sure to scrape around the sides, until most of the liquid has evaporated. Continue adding stock, a ladleful at a time, and stirring almost constantly, until the risotto has turned creamy and thick, and the grains of rice are tender with a bit of bite, about 25 to 30 minutes. Pluck out the rosemary branch and stir in the lemon zest, lemon juice, and black pepper. Taste and add more salt and lemon juice if needed. Garnish with the pistachios and optional cheese before serving.