Step 1

Heat oven to 375°F.

Step 2

Mix first 5 ingredients until blended. Beat butter, sugars and peanut butter in large bowl with mixer until light and fluffy. Add egg and vanilla; mix well. Gradually add flour mixture, mixing well after each addition. Stir in chocolate.

Step 3

Drop heaping tablespoonfuls of dough, 2 inches apart, onto baking sheets.

Step 4

Bake 10 to 12 min. or until lightly browned. Cool 1 min. on baking sheet; remove to wire racks. Cool completely.