With an electric mixer, beat butter and sugars on medium-high speed until fluffy, about 2-3 minutes.
Blend in pumpkin, egg and vanilla. Add flour, baking powder, cream of tartar, salt, cinnamon and nutmeg. Mix just until combined. Cover and chill dough for an hour.
When ready to bake, preheat oven to 350 degrees F. Line baking sheets with parchment paper.
In a small bowl, combine sugar, cinnamon, ginger and allspice for rolling. Set aside.
Roll 1 tablespoon of cookie dough into a ball. Roll into cinnamon-sugar coating and place on prepared baking sheets, 2 inches apart. Flatten cookie dough balls with a heavy bottomed glass or measuring cup.
Bake for 10-12 minutes, or until puffy and golden. Let cool on baking sheets for 5 minutes, then transfer to a wire rack.
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