In a large bowl, cream butter and sugar until light and fluffy. Add eggs, one at a time, beating well after each addition. Add pumpkin. Combine the flour, pie spice, baking powder, cinnamon, salt, baking soda and ginger; add to the creamed mixture alternately with buttermilk, beating well after each addition.
Fill paper-lined muffin cups three-fourths full. Bake at 350° for 20-25 minutes or until a toothpick inserted in the center comes out clean. Cool for 10 minutes before removing from pans to wire racks to cool completely.
For frosting, in a large bowl, beat cream cheese and butter until fluffy. Add the confectioners’ sugar, vanilla and cinnamon; beat until smooth. Frost cupcakes. Refrigerate leftovers. Yield: 2 dozen.