In a large resealable bag, mix together soy sauce, water, honey, brown sugar, garlic, and vinegar. Add chicken drumsticks and marinate in the fridge for one hour.
Preheat the oven to 425 degrees.
Set an oven-safe skillet over medium-high heat on the stove (you want it to be hot enough to sear the chicken skin). Place the drumsticks in the skillet and reserve the marinade. Brown the chicken, turning to brown all sides (about 7 minutes total).
Once the chicken is browned, add the marinade to the skillet, stir everything around, and add to the preheated oven.
Bake until the chicken is cooked through, about 20 minutes (a thermometer inserted into the thickest part will read 165 degrees).
Remove from the oven, sprinkle with parsley, and serve.