Allow butter and eggs to stand at room temperature for 30 minutes. Add cupcake liners to cupcake pan and set aside. In a medium bowl stir together flour, baking powder, cinnamon, baking soda, nutmeg, cloves and ginger aside.
In a mixing bowl beat butter with an electric mixer on medium to high-speed for 30 seconds. Add sugar and vanilla, until combined. Add eggs one at a time, beating well after each addition. Combine pumpkin and buttermilk in a bowl. Set aside. Alternately add flour and buttermilk/ pumpkin mixture to the butter mixture, beating on low speed after each addition just until combined. Then pour into cupcake molds.
Bake in a 350° oven for 15 to 20 minutes or until a wooden toothpick inserted near center comes out clean. Remove from oven and place directly into freezer for 15 minutes, don't leave them too long because you don't want them to freeze. This will make the cupcakes very moist.
For the frosting: In a large bowl, beat together the butter and cream cheese with an electric mixer. With the mixer on low speed, add the powdered sugar a cup at a time until smooth and creamy. Beat in the vanilla extract. Spread on cooled cupcakes.