Heat oven to 350 degrees. Mix rices, 3/4 cup of the alfredo sauce, 1/4 teaspoon of the tarragon and the pepper in ungreased 13x9x2 inch baking dish.
Spray 12 inch nonstick skillet with cooking spray; heat over medium high heat. Sprinkle chicken with seasoned salt. Cook chicken in skillet 3-4 minutes, turning once, until brown. Place chicken on rice mixture.
Mix remaining alfredo sauce, remaining tarragon, the asparagus, mushrooms and bell peppers. Spoon over chicken and rice. Cover and bake for 1 hour or until juice of chicken is no longer pink when centers of thickest pieces are cut.
Makes 6 servings.