Wash the beef and pork belly, drain, and finely mince or grind them in a food processor.

Steam the betel leaves for 1 minute to make them easier to roll. You can skip this step, but if you do, use skewers to help hold the rolls together when wrapping the meat.

To make the dipping sauce: In a bowl, combine 1 cup fermented anchovy sauce (mắm nêm) with juice from 1/2 pineapple (grate or mash to extract juice). Mix in sugar, MSG, minced chili, and garlic to taste.

Lightly sear the wrapped betel leaf rolls in a skillet. Then, you can grill them over charcoal or continue pan-searing over low heat for about 4 minutes until the meat is cooked and firm. Serve with rice vermicelli noodles or bánh hỏi, assorted greens, cucumber, and dip in the mắm nêm sauce for the best flavor.