Take the fresh beaten dahi in a bowl and add grated onion, turmeric powder, salt, sugar, red chilli powder, and grated ginger.
Mix the ingredients to a paste and dip the fish pieces in the paste. Refrigerate it for 1 hour to marinate.
Crush the cloves, cinnamon stick, and the green cardamom to a coarse powder.
Heat mustard oil in a wok, add one dried red chili first and then the coarse powder.
Sim the flame and add the marinated fish along with dahi paste, cover the wok with a lid and let it cook for 10-15 minutes.
Note: Do not add water while cooking. Also, do not turn around the marinated fish while it is being cooked.