Marinate: Combine chicken, soy sauce, half the garlic and peppercorns in a bowl. Cover and marinate overnight in the refrigerator. The longer it sits the deeper the flavor. Sear: Heat oil in a heavy pot over medium-high heat. Remove chicken from marinade and reserve the liquid. Brown chicken on both sides, about 2 to 3 minutes per side. Set chicken aside.
Build the base: In the same pot add remaining garlic and ginger. Saute until fragrant, about 30 seconds.
Simmer: Return chicken to the pot. Pour in reserved marinade and water. Bring to a boil then reduce heat. Cover and simmer for 35 to 45 minutes. Native chicken needs the full time.
Add vinegar: Pour in the Datu Puti without stirring. Let it boil untouched for 2 to 3 minutes then stir gently. Add brown sugar. Finish: Simmer uncovered another 10 to 15 minutes until sauce reduces. Taste and add salt only if needed. Serve with lots of rice.