1. Heat oil in a wok over medium heat. Add red curry paste and sliced porks.
2. Stir fry until the pork is nearly cooked. Then add garcinia leaves (squash the leaves before add in the wok).
3. Season with fish sauce, sugar and tamarind concentrate. Stir until all ingredients mixed well. Then turn down to low heat and let simmer for 30 minutes or more (during simmering, if the liquid is very low, add more water).
4. Transfer to a serving bowl, Serve immediately with hot steamed rice.