In large bowl, beat ½ cup granulated sugar, the brown sugar, peanut butter, butter and egg with electric mixer on medium speed, or mix with spoon, until well blended. Stir in flour, baking soda and baking powder until dough forms.
Roll dough into 1 inch balls then into the additional sugar. Put them 2 inches apart on an ungreased cookie sheet.
Bake 8-10 minutes until the edges are brown. Use a small spoon and indent the middle. Let cool on a cooling rack.
Once fully cooled. Pipe some chocolate dots in the middle of the cookie then stick the milk duds in. Use some for the candy eyes then draw legs coming out of the body.