Preheat oven to 350F. Line cookie sheets with parchment paper or leave ungreased. Combine peant butter, sugar and egg in medium bowl until blended and smooth.
Shape dough into 24 balls about 1 1/2 inches in diameter. Place 2 inches apart on cookie sheets. Press one chocolate star on top of each cookie. Bake 10 to 12 minutes or until set. Transfer to wire rack to cool completely. Makes 24