Add egg whites to a medium mixing bowl. Combine in a separate mixing bowl or gallon size zip lock bag, flour, ½ teaspoon black pepper and cayenne pepper. One at a time, dip chicken into egg whites and allow excess to drip off.
Next, coat both sides of chicken pieces in flour mixture. Heat oil on medium heat until a small amount of flour dropped in sizzles…indicating oil is hot enough. Add chicken and lightly brown on both sides. Remove from oil and drain on a paper towel.
Preheat oven to 375 degrees.
In the same skillet, sauté onion, garlic and bell pepper until tender, about 5 minutes. Add all ingredients, except chicken, to a 9” x 13” casserole dish, stir to combine. Place chicken in the rice mixture, loosely cover with foil and bake approximately 60 minutes or until rice is tender and has absorbed most of the liquid.