Cut onion and garlic cloves into small cubes and sauté together with cinnamon, cardamom, curry or bay leaves in a little clarified butter or ghee.
Rinse the fish well, cut into large pieces and add. Add water, vinegar and turmeric and simmer over medium heat until the fish is almost cooked.
Add the juice of one lemon and the ground mustard seeds and let everything simmer for about 10 minutes.
If you like the sauce a little bit thicker, you can add a little bit of yogurt.
Tip: Use regular or light yogurt as needed!