Add oil in a pan. Add salt and turmeric to fish and potato pieces and fry and keep aside.

Add kalonji and green chillies to oil. Add potato.Mix turmeric,salt,ginger together and add1 tbsp water. Add it to oil. Cook for 1 minute and add 1 glass and 1 cup water to it. Let it boil for 2 minutes. Add fish and boil for 7 minutes. Sprinkle coriander leaves. Ready to serve.