Cut the pork belly into bite-sized pieces. Finely puree the onions and garlic together with the fish sauce, turmeric, ginger, paprika powder and chillies or chilli powder with a hand blender. Marinate the meat with the seasoning paste for at least 1/4 hour.
Sear the meat in hot vegetable oil for four to five minutes on all sides, then let it take on a strong color over a medium flame for another five minutes.
Pour half a liter of water and bring to the boil. Cover and simmer on a low flame for an hour until the meat is very soft. If necessary, add more water and / or extend the cooking time.
Finally mix in the tamarind sauce. If you like it a bit more sour, you can also add three or four spoons. Season to taste with salt or fish sauce. It is served with rice, of course.