Preheat the oven to 400°F (207°C). Pat the chicken thighs dry with paper towels.
In a bowl, whisk together the soy sauce, honey, sriracha, sugar, sesame oil, minced garlic, and a pinch of salt to make the marinade.
Place the chicken thighs in the bowl and toss to coat evenly with the marinade. Let sit for 15 minutes.
Line a baking sheet with parchment paper or foil and transfer the chicken and all marinade onto it. Cover loosely with foil to prevent burning.
Bake for 20 minutes, or until the chicken is cooked through (no pink and juices run clear).
Remove the foil, spoon the pan juices over the chicken, then broil for about 1 minute to char the surface; watch closely to avoid burning.
Remove from the oven, slice the chicken if desired, and garnish with white sesame seeds and chopped scallion before serving.