Place the meat in a pot and partially cover it with water. Add the bay leaf, garlic, a generous pinch of salt, and some pepper.
Cover and simmer over medium heat for 20-30 minutes until the meat becomes tender and most of the water has evaporated.
Remove the cover and allow the remaining water to evaporate. Render the fat from the pork and cook until golden brown, tossing it constantly. Be careful, as they may splatter.
Transfer the meat to a plate and remove excess pork fat.
Saute onion and garlic until softened, about 2 minutes.
Add the ripe tomatoes and continue sautéing until they caramelize, about 3 minutes. Add more oil, if needed.
Add half of the green chilies and the shrimp paste, then sauté for about a minute.
Add the coconut milk or water, then mix them while scraping the fond or browned bits from the bottom of the pot. Taste to see if it needs fish sauce or a little sugar to balance the flavors.
When it starts to simmer, return the meat back to the pot and mix them together.
Cover and cook for another 5 minutes, allowing it to absorb all the delicious flavors.
Add the rest of the chili peppers, then turn off the heat.