Wash peppers, and cut into long-large strips. Cut onion into 4 segments. Cut chicken into one inch strips.
Layer everything in the crockpot, starting with the salsa, chicken breasts, seasoning, lime juice, peppers, and onion. Cover and cook on low for 6-7 hours or on high for 3-4 hours, or until chicken is cooked through and peppers are tender.
Remove chicken and vegetables from the crockpot and serve on warmed tortillas (or lettuce wraps) and serve with toppings of choice.
If you don’t own a crockpot, spray large non-stick skillet with non-stick cooking spray. Cook chicken over high heat stirring until browned on all sides (about 6 minutes). Reduce heat to medium and add the peppers onion and seasoning to chicken. Add 1/2 cup water and mix well. Cover for about 2 minutes, to steam the peppers and onion, and remove, stirring until water evaporates and onions and peppers are tender and sauce is thickening. Stir in salsa, and serve on tortillas