Preheat the oven to 400 degrees F; line a baking sheet with parchment paper. Whisk the flour, baking powder, sugar, salt and nutmeg in a large bowl. Whisk in 1 tablespoon parmesan. Add the diced butter and work it in with your fingertips until the mixture looks like coarse crumbs. Mix the pumpkin and cream in a small bowl and pour over the flour mixture. Mix with your hands or a fork to make a soft dough.
Turn the dough out onto a lightly floured surface and roll out into a 3/4-inch-thick rectangle using a floured rolling pin. Cut out biscuits using a 2-inch-round cutter and arrange about 2 inches apart on the prepared baking sheet. Brush the tops with melted butter and sprinkle with the remaining 1 tablespoon parmesan. Bake until golden, 15 to 20 minutes. Transfer the baking sheet to a rack and let the biscuits cool slightly before serving or cool completely and freeze (see Cook's Note).
Make It Ahead: Let the biscuits cool completely, then freeze in a resealable plastic bag for up to 1 month. To reheat, arrange on a baking sheet, cover with foil and bake at 350 degrees F until warmed through, about 10 minutes.