1Cut chicken into 1/4" slices. Place chicken in mixing bowl with half of the seasoning, 1 tsp olive oil and salt and pepper to taste. Let chicken marinate at least 10 minutes.
2Place large non-stick pan over medium high heat with 1 tsp olive oil. Add marinated chicken. Let sit undisturbed 3-4 minutes, until slightly charred. Stir and cook until browned, 2 minutes.Transfer chicken to plate. (Chicken will finish cooking in a later step.)
3Return pan used to cook chicken to medium-high heat. Add sliced vegetables. Cook undisturbed until slightly charred, 2-3 minutes. Remove from heat and mix with remaining seasoning and pinch of salt and pepper.
4Return pan with vegetables to medium-hight heat. Add chicken and cook until chicken reaches minimum internal temperature of 165 degrees, 2-3 minutes.
5Remove from heat and serve with tortillas, cheese and sour cream.