Soak wooden skewers in water 30 minutes to prevent burning.
Thread pork, peppers, and onions alternately onto skewers. Sprinkle kabobs evenly with seasoned pepper; lightly coat with cooking spray.
Grill kabobs, covered with grill lid, over medium heat (300° to 350°) 6 to 8 minutes on each side or until done. Garnish, if desired.
Cajun Turkey Kabobs: Substitute 1 1/2 lb. turkey tenderloin for pork loin and 2 Tbsp. Cajun seasoning for seasoned pepper. Proceed with recipe as directed.
Caribbean Pork Kabobs: Substitute 1 1/2 lb. pork tenderloin for pork loin and 2 Tbsp. Caribbean Jerk seasoning for seasoned pepper. Proceed with recipe as directed. Squeeze juice from 1 large lime over kabobs just before serving.
Spicy Chicken Kabobs: Substitute 1 1/2 lb. chicken tenderloin for pork loin. Whisk together 1/3 cup peanut butter, 1/3 cup water, 1/4 cup soy sauce, 3 Tbsp. brown sugar, 3 minced garlic cloves, 1 Tbsp. grated lime rind, and 1 tsp. dried crushed red pepper flakes. Place chicken in a large zip-top plastic bag; pour peanut butter mixture over chicken. Seal bag, and chill at least 30 minutes or up to 4 hours. Remove chicken from marinade, discarding marinade. Proceed with recipe as directed.