Preheat the oven to 400°F.
Peel the butternut squash, remove the seeds, and cut it into 3/4-inch cubes. You should have about 6 cups.
Place the squash on a sheet pan and toss it with the olive oil, 1 teaspoon salt, and 1/2 teaspoon pepper.
Roast for 25 to 30 minutes, tossing once, until very tender.
Set aside.

Meanwhile, heat the chicken stock in a small covered saucepan.  Leave it on low heat to simmer.  
In a heavy-bottomed pot or Dutch oven, melt the butter and sauté the pancetta and shallots on medium-low heat for 10 minutes, until the shallots are translucent but not browned.
Add the rice and stir to coat the grains with butter.  
Add the wine and cook for 2 minutes.
Add 2 cups of stock to the rice plus the saffron, 1 teaspoon salt, and 1/2 teaspoon pepper.
Stir and simmer until the stock is absorbed, 5 to 10 minutes.
Cook, stirring until the mixture seems a little dry, then add 2 more cups of stock.
Continue until the rice is cooked through, but still al dente, about 30 minutes total.
Off the heat, add the roasted squash cubes and Parmesan.
Mix well and serve.