In a large bowl, cream butter and sugar until light and fluffy. Beat in the eggs, sour cream and vanilla. Combine dry ingredients; gradually add to creamed mixture and mix well.
Drop by tablespoonfuls onto ungreased baking sheets. Bake at 375° for 10-12 minutes or until edges are lightly browned. Remove from pans to wire racks to cool completely.
For frosting, in a large bowl, combine the confectioners' sugar, butter, milk, vanilla and food coloring. Frost cookies.
Cut sugar wafers into triangles; place two on each cookie for ears. With a toothpick, poke two holes in each marshmallow half for nostrils; press butterscotch chips into holes. Place noses on cookies; add chocolate chip eyes. Yield: 6 dozen.