This fun twist on barbecue chicken borrows flavors from a Chinese takeout favorite. We grill the chicken without any of the glazy sauce brushed on because you would lose all subtlety in the sauce if it were to char on the grill. The sauce gets its translucent sheen from neutral-flavored light corn syrup (not to be confused with high fructose corn syrup); you could substitute honey, brown rice syrup, or Lyle’s Golden Syrup—just know that the sauce will be a darker color and will take on the flavor of the sweetener.
How to Make It
Place chicken, breast side down, on a cutting board. Using kitchen shears, cut along both sides of backbone; remove and discard backbone. Turn chicken breast side up; press firmly against breastbone with heel of your hand, splaying chicken open and flattening it slightly, butterfly style. Trim excess fat. Combine soy sauce and oil in a large ziplock plastic bag; add chicken. Seal bag; chill 1 to 2 hours. Drain chicken; discard marinade. Pat chicken dry.
Whisk together ketchup, corn syrup, vinegar, garlic, crushed red pepper, and 1/4 teaspoon salt until smooth. Set aside.
Preheat a gas grill to high (450°F to 550°F) on one side, or push hot coals to one side of a charcoal grill. Place chicken, breast side down, on oiled grates over lit side of grill. Grill chicken, uncovered, rotating (but not flipping) often, until skin is crispy, 6 to 8 minutes. (Make sure to keep rotating chicken to prevent flare-ups.) Place chicken, breast side up, over unlit side of grill, and grill, covered, until a thermometer inserted in thickest portion registers 165°F, about 35 minutes.
About 10 minutes before chicken is done, coat scallions and bell peppers with cooking spray. Grill, turning often, until lightly charred, 4 to 5 minutes for scallions and 6 to 7 minutes for bell peppers. Transfer vegetables to a cutting board. Cut scallions into 2-inch pieces, and cut bell peppers into strips.
Arrange grilled vegetables on a serving platter; sprinkle with remaining 1/4 teaspoon salt. Place chicken on top of vegetables, and brush chicken with 1/4 cup sauce. Sprinkle evenly with cilantro and sesame seeds, and serve with remaining sauce.