Place pork tenderloin in a bowl or zip-loc bag and pour over half of the Teriyaki sauce and toss with tenderloin until completely coated. Seal and allow to marinate for at least 30 minutes to overnight in the refrigerator.
Pre-heat grill 425°F.
Arrange pork tenderloin, zucchini, bell peppers, and onions onto skewers.
Place skewers onto grill and cook 15-20 minutes, rotating every 5 minutes. Remove from grill when internal temperature of the pork reaches 145°F. Set aside and let rest for 5 minutes.
Brush skewers with remaining Teriyaki Sauce. Garnish with sesame seeds. Serve. Enjoy.