Marinate the chicken and pork in soy sauce, vinegar, garlic and pepper, in a non-reactive bowl, for 30 minutes to 1 hour, rotating at least once. The chicken can also marinate overnight.
Place the chicken, bay leaves and marinade in a deep sided sauté pan and cook over medium heat. When the sauce is bubbling, turn the chicken and cook until the meat is nearly cooked through, about 15 minutes. Transfer the sauce to a bowl, add oil to the pan, and brown the chicken and pork on all sides, working in batches. Return the sauce to the pan, bring to a boil and lower heat to a simmer. Adjust the sauce to taste with salt and pepper. Cook for about 20-30 minutes, or until the chicken is tender and the sauce a thick and deep color.
Serve over rice.
This recipe is easily adaptable - use all chicken or all pork if you wish - and make more sauce (because to me, the sauce is the best part) by simply adding equal parts of soy sauce to vinegar. It's best served over rice, with lots of sauce!