Whisk the soy sauce, rice vinegar, sugar, and garlic in a small bowl until the sugar is completely dissolved.

Pour half of the marinade along with 2 tablespoons of water and the chicken into a 1-gallon zip-top bag or baking dish. Set the remaining half of the marinade aside.

Toss the chicken to coat, then press as much air out of the bag (if using) as possible, or cover with plastic wrap (if using a baking dish). Refrigerate for at least 30 minutes, or up to 60 minutes, flipping every 15 minutes.

When ready to grill, heat a grill to medium high. Allow to preheat for 15 minutes. Remove the chicken from the marinade, shake off any excess, and discard any remaining marinade from the bag or dish.

Grill, with the cover down, until chicken thighs register 170F or chicken breasts register 165F.

Remove to a cutting board and allow to rest for 5 minutes. Slice against the grain into ½ inch slices, and serve drizzled with reserved marinade.

Preheat your oven to 425°F. Set aside half of the marinade, then add the chicken and the remaining marinade into a small baking dish. If you have a large baking dish or rimmed sheet pan, omit the marinade as it will spread and possibly burn. Bake for 20 to 25 minutes, until or until chicken thighs register 170F or chicken breasts register 165F.

Optional: If you want a dark, caramelized color you can run the chicken under the broiler for 2-3 minutes at the end of the baking time. Note you'll need to use a broiler safe pan and watch the chicken carefully, as it will burn exceptionally easily.

Remove to a cutting board and allow to rest for 5 minutes. Slice against the grain into ½ inch slices and serve, drizzled with reserved marinade.