Place chicken or vegetable stock in a large sauce pan, then bring to a simmer until needed.
Heat ½ Tbsp butter over medium-high heat in a large pan or pot. When hot, add pancetta then cook, stirring often, until browned and crispy on all sides, about 3-4 minutes. Use a slotted spoon to transfer pancetta to a paper towel lined plate or bowl.
To the same pan, add minced shallot. Cook until translucent, about 2 minutes, then add grated butternut squash, rice, and garlic. Cook for 3 minutes, stirring often.
Pour in wine, then allow to cook for 1-2 minutes until most of it has evaporated. Begin adding stock 1-2 ladlefuls at a time, stirring constantly. After a couple minutes, most of the stock should have been absorbed by the rice. Repeat, adding more stock and stirring continuously, until the rice is creamy, yet tender, about 20 minutes total. Variation in cook time may be due to the size of your pan or the temperature. You want the rice to be al dente with just the slightest bite. The risotto should move freely around the pan and be more soupy than dry.
Add remaining butter, ground cinnamon (if using), Parmigiano Reggiano, sage, lemon zest, and cooked pancetta to the risotto, then stir to combine. Taste, then add kosher salt as needed to season. Immediately divide between bowls, then serve with cracked pepper and extra Parmigiano Reggiano on top.