The Holidays call for 2 things in my book… pumpkin and buttercream. One of my favorite pumpkin treats is Trader Joes Pumpkin Butter.  It is a little sweet with a little spice making it AMAZING!   When you add it to this buttercream recipe it is AMAZING! Not your normal filling I love a good sandwich cookie with a  good filling.   I love the richness and creaminess it brings to anything and everything you add it to.  Most of the time buttercream is used on cakes and cupcakes, but this time I used it as the filling for my new favorite cookie.  Yes cookie my Spiced Molasses Sandwich Cookies. If…