In microwavable bowl, microwave baking chocolate uncovered on High 1 minute or until melted, stirring after 30 seconds. Stir in hazelnut spread until well blended. With fork, dip brownie balls, one at a time, into chocolate mixture; tap off excess. Return to cookie sheet. Sprinkle with remaining 1/4 cup hazelnuts. Refrigerate 30 minutes or until set.