In a wide pan over medium heat, heat oil. Add onions and garlic and cook until softened.
Add pork and cook, turning as needed, until lightly browned. Cook, stirring occasionally, for about 7 to 10 minutes.
Add chicken and cook, stirring occasionally, until lightly browned and juices run clear.
Add vinegar and bring to a boil, uncovered and without stirring, for about 2 to 3 minutes.
Add soy sauce, water, and bay leaves. Continue to boil for about 2 to 3 minutes.
Lower heat, cover, and cook for about 30 to 40 minutes or until meat is tender and sauce is reduced.
Season with salt and pepper to taste. Serve hot.