Season chicken with salt and red pepper. In a large, nonstick skillet, cook chicken in hot oil for 3 to 4 minutes. Add sweet potato and banana pepper. Cook and stir for 5 to 6 minutes more or until chicken is no longer pink and potato is just tender. In a small bowl stir together the pineapple juice and cornstarch; stir into chicken mixture. Cook and stir gently until slightly thickened and bubbly. Stir in bananas. Cook and stir 2 minutes more. Serve over cooked brown rice. Makes 4 main-dish servings.