Heat 1 cup water in a non-stick pan, add gorake and mix well. Cook till the gorake becomes soft. Drain and reserve the water in a bowl.
Slice ginger, roughly chop green chilli and break cinnamon stick and put them in a mixer jar. Add cooked gorake and ½ cup water and grind to a smooth paste.
Place banana leaf pieces in a clay pot.
Put the ground paste into the bowl with gorake water, add fish pieces and mix well. Add salt and half the curry leaves. Roughly chop remaining curry leaves and add along with 2-3 tbsps water and mix well.
Put the fish into the clay pot over banana leaf pieces, roughly tear and place coriander sprigs over it.
Place the clay pot on heat and cover with its lid. Cook till the fish is done.