In a medium bowl, toss with the olive oil, kosher salt, and fresh ground pepper. Line a baking sheet with parchment paper, then pour the squash on top in an even layer. Roast 30 to 35 minutes until tender and browned, turning once.
Meanwhile, mince the shallots. Roughly chop the sage.
Combine the broth, water, and kosher salt in a saucepan and place over medium heat. (You’ll use this warmed broth to stir into the risotto).
Heat the olive oil and butter in a large skillet over medium heat. Add the shallot and cook for 5 to 6 minutes until tender. Add the chopped sage, garlic powder, and rice and cook, stirring occasionally, about 2 minutes until the rice starts to turn light brown. Stir in the wine and cook until the liquid is fully absorbed.
Add two ladles of the hot broth to the risotto. Cook, stirring occasionally until the liquid is fully absorbed, then add two more ladles of broth. Cook in this same manner for about 12 minutes, adding two ladles and stirring. After the 12 minutes, taste a grain of rice. If it’s creamy but still al dente in the center, you’re ready for the final step! If not, continue to cook and add broth for a few minutes more.
When the rice is al dente, reduce the heat to low. Add two more ladles of broth, the Parmesan cheese and a few grinds of black pepper. Stir vigorously for 1 to 2 minutes until you’ve got a thick and creamy risotto. Then stir in the butternut squash serve immediately. (Note that there will be some broth left over: this is expected! You can save and use it to stir into leftovers to return it to a creamy texture.) Stores refrigerated in a sealed container for 3 days; reheat before serving.