- Make the sauce: In a stainless-steel saucepot over medium-low heat, whisk together brown sugar, garlic, ginger, orange zest, ¾ cup orange juice, soy sauce, rice wine vinegar, and sesame oil. Increase heat to medium-high and bring sauce to a boil.
- Meanwhile, in a small bowl, whisk together remaining ¾ cup orange juice with cornstarch until cornstarch has fully dissolved. When sauce reaches a boil, slowly pour in cornstarch mixture while whisking sauce continuously. Boil for 1 to 2 minutes more, then reduce heat to low and allow to simmer for 5 minutes. Strain sauce through a fine mesh strainer, then stir in red pepper flakes and salt. Set aside.
- Fry the chicken: In a 5-quart dutch oven over medium-high heat, bring oil to 325 degrees. Carefully lower drumsticks into oil and fry until cooked through, about 15 to 20 minutes.
- While drumsticks are frying, combine ginger, garlic powder, and onion powder in a small bowl. Carefully remove drumsticks from oil and transfer to a stainless-steel bowl. Add spice mixture, orange sauce, and black and white sesame seeds; toss to evenly coat. Garnish drumsticks with more sesame seeds and scallions.