Soak mushrooms & asam in water till soft.
Clean fish & cut off Pectoral Fins (optional). Make 2-3 slits on each side. Marinade fish. Insert small amount of ginger, chilli & mushrooms into slits. Put some ginger into cavity too.
Make a double layer foil boat & place some ingredients on it. Put the boat over another layer of foil for wrapping later.
Place fish on top of ingredients & add the rest around it. Mix seasonings with water & pour it in.
Wrap foil tightly. Leave the fish in the fridge to marinade for about 15 mins. Steam fish for about 20 mins since it’s from the fridge.
Check to see if fish is cooked by inserting a toothpick. Fish is ready to be served if it pierces through easily. Transfer to serving plate & unwrap foil. Garnish with spring onions & serve piping hot. * Reduce time by 5 mins if you steaming directly from a plate without foil. Enjoy!