Ingredients

• 1 lb banana leaves, thawed if frozen (see cooks' note, below)
• 3 tablespoons vegetable oil
• 2 tablespoons Thai red curry paste
• 3 tablespoons Thai chicken stock or canned chicken broth
• 2 tablespoons nam pla (Asian fish sauce; preferably Thai)
• 1 1/2 lb catfish fillets, cut into 1-inch cubes
• 1 1/2 tablespoons toasted rice powder
• 3 (4-inch-long) fresh or frozen Kaffir lime leaves (sometimes called bai makroot), very thinly sliced
• Special equipment: a large (6-qt) wok with lid; a heatproof plate (just small enough to fit inside steamer rack); a large steamer rack

Instructions

1. Unfold banana leaves. Cut off and reserve tough center rib that runs along bottom edge of each leaf with kitchen shears. Cut ribs into 12-inch strips (you'll need 8) for tying packets. Gently cut leaves into 8 (10-inch) squares with shears, being careful not to split them (you may want to cut a few extra in case some split while folding). Gently wash banana leaf squares in a large pan of water, then pat dry.
2. Heat oil in wok over moderate heat until warm, about 30 seconds, then cook curry paste, stirring constantly, until very fragrant and a shade darker, 1 to 2 minutes. Add stock and fish sauce and bring to a boil over high heat, stirring. Add fish and rice powder and stir-fry until outside of fish just turns white, 1 to 2 minutes, then transfer mixture to a bowl.
3. Put a banana leaf square on a work surface, then put 1/3 cup fish curry in center of square and sprinkle with some of sliced Kaffir lime leaves. Fold 2 sides of banana leaf over fish to enclose it (be careful not to split leaf), then fold in opposite sides to form a packet. Tie packet with a strip of banana leaf rib and transfer to heatproof plate. Assemble 7 more packets in same manner, arranging in 1 layer on plate.
4. Bring 1 inch water to a boil in wok fitted with steamer rack. Transfer plate with packets to steamer rack carefully and steam, covered with lid, 5 minutes. Serve packets warm or at room temperature.