Step 1

Heat oven to 350°F.

Step 2

Chop 8 oz. chocolate coarsely; set aside. Microwave remaining chocolate in large microwaveable bowl on HIGH 2 min., stirring after 1 min. Stir until chocolate is completely melted. Add butter; stir until melted. Add peanut butter, sugar, eggs and vanilla; stir until blended. Add flour and baking powder; mix well. Stir in chopped chocolate and nuts.

Step 3

Drop rounded tablespoonfuls of dough, 3 inches apart, onto baking sheets sprayed with cooking spray.

Step 4

Bake 12 to 14 min. or until cookies are puffed and feel set to the touch. Cool on baking sheets 1 min. Remove to wire racks; cool completely.