1Heat oven to 350°F. Spray 8-inch square pan with cooking spray (without flour).
2In small bowl, mix brown sugar and hazelnut spread. Stir in nuts and chocolate chips; set aside for topping.
3In large bowl, stir flour blend, baking powder and salt; set aside. In medium bowl, beat eggs and granulated sugar with whisk until smooth. Stir in butter and vanilla. Stir into flour mixture just until combined. Pour batter into pan. Sprinkle with reserved topping mixture.
4Bake 25 to 27 minutes or until toothpick inserted in center comes out clean. Serve warm.