Thai steamed fish with chilli & lime, or Plah Neung Manao, is a fresh, light and healthy dish which is incredibly popular in Thailand.
Cut 3–5 diagonal slashes across the fish, about 1 1/2 inches apart on both sides, using a very sharp knife.
Put lemongrass, red onion, coriander and garlic into cavity of the fish. Cover a heatproof plate which is smaller then the steamer by a few inches, with banana leaf or foil, so that the steam can circulate around the fish. Place the fish on top of the banana leaf or foil covered plate.
Bring 2 inches of water to boil over high heat in the bottom of the steamer. Reduce the heat to medium before removing the lid from the steamer, lifting the lid away from you and allowing the steam to dissipate before placing the plated fish onto the top rack of the steamer. Cover and steam for 10–12 minutes. If you plan to use the heated platter, undercook the fish somewhat but if you are serving it directly on a plate, then steam until cooked through.
While the fish is steaming, in the Pestle and Mortar or Food processor, place chopped garlic, chilli peppers, cilantro, chicken broth, fish sauce, lime juice and sugar and crush/mix. Taste to adjust seasoning – the taste should be a balance of spicy, salty and sour. Set aside.
When the fish is cooked to the desired degree, remove the steamer from the heat and transfer the hot fish to a Thai Fish-shaped Heated Serving Dish or serving plate.