This recipe illustrates the popular use of banana leaves as a food wrapper in Asia. Aluminum foil works well as a substitute. IN A MINI-FOOD PROCESSOR, add the garlic, peppercorns, coriander root and ginger; process into a fine mince. Transfer into a mortar and pound into a smooth paste; add soy sauce and blend thoroughly. Clean fish and pat dry with paper towel. Rub garlic mixture over entire fish; set aside for 30 minutes. Choose a banana leaf about 6 inches longer and 3 times wider than the fish. Rinse leaf with cold water to clean. Plunge leaf into a pot of boiling water for a few seconds to soften. Wipe dry. Using a knife or scissors, remove the thick spine in the leaf. Place the leaf with its glossy side down on a work surface. (Use more leaves if needed.) Brush oil on the leaf where the fish will lie. Set the fish with the marinade on the oiled surface. Fold over the wide sides overlapping at the top and secure with toothpicks. Turn over package, fold over ends to enclose sides, and secure ends with toothpicks to make a neat parcel. Set packet about 3 inches above medium-high heat coals and grill each side for 8 to 10 minutes. NOTE: If using trout, marinate the 4 fish together. Wrap each 1 individually and reduce the grilling time to about 3 minutes on each side. Serves 4 as part of an Asian multicourse menu. Transfer to a serving plate. Open leaf and serve with accompanying sauce. CHILE LIME SAUCE: In a mortar or a mini-food processor, add the chiles, garlic, coriander leaves, sugar and salt; pound (or chop) into a smooth paste. Put chile mixture into a saucepan with lime juice and stock; bring ~-