Cream together butter and 4 tablespoons powdered sugar. Blend in flour, then nuts, vanilla, and water.
Scoop tablepoon-sized balls and place on ungreased cookie sheets. Chill at least 2 hours. Bake at 375°F until lightly browned.
Cool slightly, then roll each cookie in powdered sugar. Allow to cool completely on wire rack, then roll again in powdered sugar.
