In a large bowl, beat the butter and sugar together until creamy.
Beat in the pumpkin, egg, and vanilla.
On top add the flour, baking powder, soda, spices, and salt. Mix until combined.
Place on a parchment lined baking sheet and bake for 10-12 minutes. Remove and allow to completely cool.
Meanwhile, beat together the room temperature butter and cream cheese with the powdered sugar and vanilla. Add the powdered sugar to desired consistency but note that the frosting is supposed to be like a non-baked cheesecake layer -- very thick and cheesecake-like.