Heat oven to 375°F. Remove wrappers from chocolate pieces.
Beat sweetened condensed milk and peanut butter in large bowl until smooth. Add baking mix and vanilla; blend well. Shape into 1-inch balls; roll in sugar. Place 2 inches apart on ungreased cookie sheets.
Bake 6 to 8 minutes or until very lightly browned (do not overbake). Remove from oven; immediately press chocolate piece in center of each ball. Remove from cookie sheet to wire rack. Cool completley. Store in tightly covered container. About