Preheat oven to 350°F. Spray Whoopie Pie Pan with vegetable pan spray.
In medium bowl, combine flour, cinnamon, baking soda, baking powder, salt, nutmeg and cloves. In large bowl, beat butter and granulated sugar with electric mixer until fluffy. Add eggs, one at a time, beating well after each addition.
Add flour mixture to butter mixture alternately with pumpkin and buttermilk, mixing thoroughly after each addition.
Fill pan 1/2 full, spreading batter to edges of cavities.
Bake 7-9 minutes or until toothpick inserted in middle comes out clean. Cool in pan 5 minutes; remove to cooling rack. Cool completely before filling.
For filling, beat cream cheese, confectioners? sugar and vanilla together until well combined. To assemble, spread filling on one cake and sandwich with another.