In a bowl, combine soy sauce, vinegar, minced garlic, black peppercorns, and laurel leaves. Add chicken thighs and marinate for at least 30 minutes, preferably overnight in the refrigerator.

Heat oil in a large pot over medium heat. Remove chicken from the marinade (reserve marinade) and brown the chicken on all sides, about 5-7 minutes.

Pour the reserved marinade and water into the pot. Bring to a boil, then reduce heat to low and cover. Simmer for 30-35 minutes or until chicken is tender.

If desired, add sugar to balance the flavors and stir well. Cook for an additional 5 minutes uncovered to thicken the sauce.

Serve hot over steamed rice, garnished with chopped green onions if desired.