Mix barbecue sauce and mayonnaise; cover. Refrigerate until ready to use.
For each serving: Toss 2 cups of the salad greens with 4 oz. chicken, 2 Tbsp. corn, 2 Tbsp. red peppers and 1-1/2 Tbsp. onions in large bowl. Add 1/4 cup of the barbecue sauce mixture; toss to coat. Spoon onto serving plate.