Step 1

Microwave butter and 4 oz. chocolate in large microwaveable bowl on HIGH 2 min. or until butter is melted. Stir until chocolate is completely melted and mixture is well blended.

Step 2

Add granulated sugar; mix well. Blend in eggs and vanilla. Add flour; mix well.

Step 3

Refrigerate 1 hour.

Step 4

Heat oven to 350ºF. Shape dough into 64 (1-inch) balls; place 2 inches apart, on baking sheets sprayed with cooking spray.

Step 5

Bake 8 min. or just until centers of cookies are set. (Do not overbake). Cool on baking sheet 2 min. Press indentation into center of each cookie. Remove to wire racks. Cool completely.

Step 6

Mix 1/2 cup peanut butter and powdered sugar in medium bowl until blended. Add 1/4 cup nuts; mix well. Spoon into indentations in cookies, adding about 1/2 tsp. peanut butter mixture to each.

Step 7

Microwave remaining chocolate and peanut butter in small microwaveable bowl 1 to 2 min. or until completely melted when stirred; drizzle over cookies. Sprinkle with remaining nuts. Let stand until chocolate-peanut butter drizzle is firm.