This portion of the recipe can be done a day in advance. Place chicken breast and bouillon cubes in stock pot with enough water (6-8 cups) to cover. Stew over medium heat for 1 1/2 hours, or until done. Reserve stock with chicken breast. Let cool. Place chicken breast and reserved stock in refrigerator until ready for use. Remove chicken breast from reserved stock and pat dry. In a mixing bowl, combine flour, 1/2 teaspoon salt, and pepper. Coat pre-cooked chicken breast with flour mixture. Melt butter in a large skillet over medium heat, and brown chicken on all sides. Remove from skillet and drain on paper towel. In the same skillet, combine the tomatoes, water, brown sugar, vinegar, and Worcestershire sauce. Season mixture with 1 teaspoon salt, chili powder, ground mustard, celery seed, garlic, and hot sauce. Bring to a boil, reduce heat and return chicken to skillet. Cover and simmer for 20 minutes, carefully turning chicken breast once. Note: Reserved chicken stock may be kept refrigerated and used in any recipe which requires chicken broth.