Whisk the gochujang, honey, soy sauce, rice vinegar, garlic, ginger, and both oils together. Spoon 3 tablespoons into a small bowl and set it aside. That is your glaze, and it never touches raw chicken.
Pat the thighs dry and toss them in the remaining marinade. Thirty minutes in the fridge is ideal, but it works straight away too.
Air fryer: cook at 200C (400F) for 12 minutes, flipping halfway. Brush with the reserved glaze and cook 3 to 4 minutes more, until the edges char and the thickest thigh reads 74C (165F).
Oven: spread the thighs on a lined sheet pan and roast at 220C (425F) for 18 to 20 minutes. Brush with the reserved glaze and broil 2 to 3 minutes until the glaze bubbles and catches at the edges.
Rest 5 minutes, then finish with scallions and sesame seeds.