Marinate the chicken with soy sauce, pineapple chunks and its juice.
Marinate overnight or for at least 3 hours.
Drain excess marinade using a colander (optional). Keep the drained marinade.
Preheat cooking pot with cooking oil.
Sauté onions until soft.
Add garlic and sauté until brown.
Add chicken pieces and sauté until light brown.
Pour in the reserved marinade.
Cover and let simmer.
Add bay leaves and whole peppercorn.
Cover and cook for 35 to 40 minutes over low to medium heat.
Add white vinegar and mix while simmering.
Add brown sugar and mix.
Simmer uncovered until the sauce reduces to desired thickness.
