Cut chicken, bell pepper, red onion and pineapple into bite-sized chunks. Place in separate bowls.
Start layering ingredients onto your skewers, alternating chicken, bell pepper, red onion and pineapple chunks. Place skewers on a large plate or cutting board. Repeat until you have 5-6 full skewers. Brush all evenly with 1/4 cup BBQ sauce, and sprinkle with salt and pepper.
Preheat your outdoor gas grill or grill pan to medium-high heat. Once hot, place skewers on grill and cook on all sides until chicken is cooked and vegetables have softened, 9-10 minutes. With a clean brush, coat skewers again with 1/4 cup more BBQ sauce. Carefully remove from heat and let cool slightly.
To remove cooked skewers to a plate, slide a fork from the top to the bottom of each skewer.