You can cook and peel pumpkin ahead of time. In a blender, blend warm, cooked pumpkin with melted butter, warm heavy cream or yogurt, salt, and pepper until smooth.
NOTE: You can also use a ricer to process the pumpkin or mash it, following the same preparation as for mashed potatoes.
Right before serving, heat mixture thoroughly in a medium, non-stick saucepan, stirring often, over medium-low heat. You may or may not need a little touch of yogurt or heavy cream to soften. Place on a serving plate or bowl and sprinkle Parmesan cheese on top, if desired.
Recipe Notes
Mashed pumpkin can be prepared up to 2 days ahead and refrigerated.