Heat grill. Cut each cake slice into 6 cubes. Spread peanut butter (or cream cheese) lightly on 2 opposite sides of cake cubes. Dip coated sides in peanuts. In medium bowl, toss nectarine pieces and banana chunks with lemon juice. Thread 3 cake pieces, 2 nectarine pieces and 2 banana chunks alternately on each of 4 (12-14" long) skewers. Heat caramel topping in small saucepan until warm. When ready to grill, brush kabobs with caramel topping. Place kabobs on gas grill over medium heat or charcoal grill 4-6" from medium coals. Cook 4-7 minutes or until well heated, turning and brushing with caramel topping. Serve warm.
Broiler Method: Prepare recipe as above. Place kabobs on broiler pan; broil 4-6" from heat, for 4-6 minutes or until well heated, turning and brushing with caramel topping. Serve warm.