Preheat oven to 250 degrees Celsius.
Thoroughly clean the pork. Season with salt and grilled in a preheated oven for 1 hour.
Scrape of the charred parts and rinse with water. Set a side.
Wash the mung beans twice. Combine mung beans and water. Boil and simmer for 1 hour or until the mung beans turned out mushy and creamy.
Sauté garlic, onion and tomatoes in oil until tomatoes turned out mushy.
Add the grilled pork leg and rice wash. Boil and simmer for 1 hour.
Add the cooked mung beans and banana blossom. Let it simmer for another 20 minutes.
Add the chopped onion spring and season with fish sauce and ground black pepper.