Water; boiling Cream butter & sugar. Add flour, baking powder, and vanilla. Mix well. Shape into 2 rolls and chill. Cut into 1/4" slices bake on greased cookie sheet at 375 F for 10 minutes or until edges brown. Cool on rack. **Goes from brown to burned in a few seconds so watch carefully. Frosting: Cook butter until browned add sugar, vanilla, and small amount of boiling water. Beat to spreading consistency, and spread on cookies. ----