In a medium wok, add the pork and add 1 cup of water bring to a boil and simmer for 8 to 10 minutes or until pork are tender and all the liquid has evaporated and start to render fat.
Add more water if needed. Set aside pork on the side of wok and stir-fry garlic and onion until fragrant, stir in the pork.
Add 1/2 cup of water and add in bay leaf, peppercorn, soy sauce and vinegar. Bring to boil and simmer for 5 to 8 minutes without stirring.
Add in green long chili and add about 2 cups of water, and drizzle with cooking oil, bring to a boil and simmer for 25 to 30 minutes or until the green long chili are wilted and the liquid has turned to an oily sauce.
Season with salt and adjust to preference. Serve with lots of rice.