In a medium bowl, whisk together the olive oil, Dijon mustard, lemon juice, honey, and soy sauce until well combined and emulsified. This creates the liquid foundation that will carry all the flavors into the chicken. The mustard acts as an emulsifier, helping the oil and acidic ingredients blend smoothly rather than separate.
Add the minced garlic, ground ginger, cayenne pepper, onion powder, paprika, cornstarch, salt, and black pepper to the wet mixture. Whisk thoroughly until all spices are fully incorporated and no lumps remain, especially from the cornstarch. This creates a cohesive marinade that will coat the chicken evenly and thicken slightly as it cooks.
Pat the chicken drumsticks dry with paper towels to help the marinade adhere better. Place the drumsticks in a large ziplock bag or shallow dish and pour the marinade from Step 2 over them. Toss well to coat each piece thoroughly, making sure the marinade reaches into crevices. Seal and refrigerate for at least 2 hours, though overnight yields even deeper flavor. I find that marinating overnight transforms the texture—the acid in the lemon juice gently tenderizes the meat while the spices fully penetrate.
Remove the chicken from the refrigerator 15 minutes before cooking to bring it closer to room temperature, which ensures more even cooking. Preheat your oven to 425°F. Line a large baking sheet with foil or parchment paper for easy cleanup, then arrange the drumsticks in a single layer. Pour any remaining marinade over the chicken—this liquid will create a glaze as it cooks and infuses the meat with flavor.
Roast the chicken at 425°F for 25 minutes until the exterior begins to caramelize and brown. Flip each drumstick and return to the oven for another 10-15 minutes until the internal temperature reaches 165°F at the thickest part of the thigh. The high heat develops a beautiful golden-brown crust while the marinade reduces into a sticky, concentrated glaze. I like to rotate the pan halfway through the second roast if I notice uneven browning.
Transfer the roasted drumsticks to a serving platter and let them rest for 5 minutes—this allows the juices to settle back into the meat for maximum tenderness. Sprinkle the fresh parsley over the top just before serving for a pop of color and fresh herbaceous flavor that cuts through the rich, savory glaze.