Don’t want to use canned pumpkin purée? You can make it from scratch. Preheat oven to 400°F. Cut 2-3 pound pie pumpkin in half and remove seeds and membranes. Place cut side down on a baking sheet with high sides covered in aluminum foil. Roast for 30-40 minutes, until soft when pierced with a fork. Let cool slightly. Scoop flesh into a food processor and purée until completely smooth. Measure out ¾ cup for the ice cream; reserve the rest of the purée for another use.