PREHEAT oven to 375° F.
COMBINE flour and baking soda in small bowl. Beat butter, peanut butter, granulated sugar, brown sugar and vanilla extract in large mixer bowl until creamy. Beat in egg. Gradually beat in flour mixture. Stir in morsels.
DROP dough by rounded tablespoon onto ungreased baking sheets. Press down slightly with bottom of glass dipped in granulated sugar.
BAKE for 8 to 10 minutes or until edges are set but centers are still soft. Cool on baking sheets for 4 minutes; remove to wire racks to cool completely.
PAN COOKIE VARIATION:
PREPARE dough as above. Spread dough into ungreased 15 x 10-inch jelly-roll pan. Bake for 15 to 18 minutes. Cool in pan on wire rack.