HEAT vegetable oil in large skillet over medium-high heat. Add chicken; cook, stirring occasionally, for 4 to 5 minutes or until chicken is no longer pink. Stir in water and seasoning mix. Bring to a boil. Reduce heat to low; cook, stirring occasionally, for 4 to 5 minutes or until mixture is thickened.
Fill warmed taco shells with chicken mixture. Top with lettuce, tomatoes, cheese and taco sauce.
Note: Toppings: shredded lettuce, chopped tomatoes, shredded cheese, Thick & Smooth Taco Sauce. (The toppings have not been included in the nutritional analysis.).