Salt cubed chicken. Combine bbq sauce, pineapple juice, and olive oil in a medium bowl for marinade. Set aside 1/3 cup of marinade. Place chicken in the remaining marinade and marinate for at least 30 minutes.
If using the grill or the oven, preheat to 400 degrees. Note for grill: I used metal skewers, as they are more easily resuable. But, if using wooden skewers, soak them in cold water for at least an hour before using so they won't burn.
Cut the veggies into 1"ish squares. Toss with olive oil to coat. Cut the pineapple into 1" cubes as well.
Time to build your kabobs! It doesn't really matter what order you put on the peppers, onion, pineapple, and chicken.
GRILL - Brush grates with olive oil (if you don't, the chicken will stick!). Place kabobs on grill and grill for 5 minutes. Brush with reserved marinade. Flip, brush this side with marinade and cook 5 minutes more (chicken should be cooked through, internal temp of 165). Enjoy!
AIRFRYER - Cook at 375 for 15 minutes, adding more marinade to both sides halfway through. Flip if it's laying flat.
OVEN - Cook at 400 for 20 minutes, flipping halfway through and adding more marinade at that time to both sides. I like to cook these on a cooling rack set inside a cookie sheet, to allow the underside to cook better. After 20 minutes broil on high for 2-3 minutes each side.