1. Stir together KELLOGG'S RICE KRISPIES cereal, flour, baking powder, soda and spice. Set aside.
2. In large electric mixer bowl, beat together egg whites, bananas, oil and brown sugar until thoroughly combined. Add cereal mixture and beat on medium speed until mixed. Portion dough, using approximatley 1/4 cup measure per doughnut, onto baking sheet coated with cooking spray. Using small rubber spatula coated with cooking spray, make 1-inch hole in center of each doughnut. Sprinkle evenly with granulated sugar and nuts.
3. Bake at 400° F for 10 minutes or until doughnuts start to brown on edges. Cool on wire racks. Serve warm or cold.