• Mix butter, sugar, and eggs until well blended. 
• Add baking powder, vanilla, baking soda, salt, and sour cream and stir well.
• Add flour and gently combine.  If too sticky, add just a little more flour and refrigerate for about 30 minutes. 
• Roll out dough on a floured surface and cut with a circle cookie cutter (I used a 2 3/4 - 3 inch diameter circle cookie cutter). 
• Bake at 350 degrees for about 9 minutes (you don't want to overcook them!).

Frosting

• Combine all ingredients and mix well.  If it's too thin, add more powdered sugar and if it's too thick, add a little more milk.

Assemble the Cookies

• Frost the cookie and immediately after add the sprinkles to the top third of the cookie with red sugar crystals (we held the edge of a little bowl to cover the rest of the cookie while we sprinkled the crystals on and it gave the hat a rounded edge).
• Next, sprinkle the bottom third of the cookie with coconut (and come a little up each edge to meet the hat) to make Santa's beard. If your frosting dried quickly, you can put a drop of water on your finger and spread it on the frosting- the coconut should stick perfectly after that.
• Place a marshmallow on the end of the hat, the chocolate chips for the eyes, and the red hot for Santa's nose.