When the half of squash is slightly cooled, scoop out, and puree in a food processor until smooth. Add a tablespoon or two of stock to thin if needed. Set aside.
Add pancetta to the skillet and cook, stirring often until browned, about 10 mins. Remove from pan using a slotted spoon and place on a paper towel lined plate to drain.
Risotto requires a short grain rice (such as arborio or carnaroli). It maintains it chew, while creating a creamy texture and holds up to all the stirring.