Step 1Place the chicken in a bowl or dish. Combine the soy sauce, vinegar, crushed garlic, some peppercorns, the bay leaf and optional chile. Pour over the chicken and marinate overnight in the refrigerator.
Step 2The next day, heat the grill to medium-high. Remove the chicken from the marinade; reserve the marinade. Grill the chicken until browned, about 5 minutes a side.
Step 3Add the browned meat to a pot with the marinade and bring to a rapid boil. Boil a couple of minutes (to kill off any bacteria, or if you prefer, you can make a new batch of sauce with fresh soy sauce and vinegar). Reduce the heat and simmer the chicken until the juices run clear when the chicken is pierced with a fork, about 30 minutes. Add the sugar, then taste. The adobo should not be too sweet, but adding sugar reduces the salty taste. If the sauce tastes too strongly of vinegar, remove some of the marinade and add soy sauce. (The stew should taste strong because it will be diluted with coconut milk.) Add the coconut milk and stir until the color of the stew is light brown
Step 4Place each serving of chicken on a plate. Accompany with white rice. Spoon some of the sauce over the rice.