Make the marinate first: In a small prep bowl combine the olive oil, salt, black pepper, soy sauce, pressed garlic, grated ginger, and brown sugar.
Place the chicken wings into a gallon-sized ziplock bag, and pour the marinade over the wings. Zip up the bag and massage the sauce into the chicken. Let it marinate for at least 2 hours in the refrigerator. I recommend laying the bag flat so that the marinade is evenly distributed while it’s marinating.
Preheat the grill to medium-high heat (400 degrees F). Then grease the grill grates with oil.
Use tongs to place the marinated chicken onto the hot grill. There will be quite a bit of marinade left over, do not throw it away and save if for the next step. Flip the chicken wings every 5 minutes to ensure even cooking. Cook for a total of about 25 minutes or until the internal temperature of the chicken is at least 170 F°.
While the chicken is grilling pour the remaining marinade into a saucepan and add the cornstarch (to thicken the sauce). Bring the sauce to a steady simmer to cook out any raw meat juice.
Now brush the sauce over the wings in the last few minutes of grilling to add more tackiness and teriyaki flavor. Serve warm with a garnish or green onion and sesame seeds.