Heat oven to 375. In large bowl combine sugar, brown sugar, margarine, peanut butter, vanilla and egg; beat well. Lightly spoon flour into measuring cup; level off. Add flour, baking powder, baking soda and salt to sugar mixture; mix well.
Shape about 1/3 cup dough smoothly around each candy bar making sure bar is completely covered. Place 4 inches apart on ungreased cookie sheets. Bake at 375 for 13 to 16 minutes or until golden brown. Cool 10 minutes; remove from cookie sheets. Cool completely.