(click to enlarge)

Prep
1. Cut FISH into pieces, about 2-1/2 by 1-1/2 inches. Use rather large pieces if you use carp (see Note-1). IF you will be frying the fish (see Note-7) rub with Turmeric and Salt. Set Aside.
2. Peel POTATOES and cut into 3/4 inch cubes. Hold in cold water until needed.
3. Break CAULIFLOWER into small florettes.
4. Cut EGGPLANT into 1 inch cubes, Hold in water acidulated with a little citric acid or lemon juice until needed.
5. Peel ONION and chop small. Slice GINGER very thin and chop fine. Mix and pound to a paste in a large mortar (or use a mini-prep processor).
6. Grind Cumin, Mustard Seed and Coriander Seed. Blend into Onions mix.along with Turmeric and Chili Powder.
7. Split CHILIS lengthwise from just under the caps to the tips. Remove seed and veins only to the extent you want to control hotness.
Run   (45 min)
8. Option, see Note-7 - heat 4 T Oil in a well seasoned iron skillet (don't try this in your sauté pan) and fry fish over moderate heat turning once until lightly browned on both sides. Remove from the oil and drain on paper towels.
9. Measure 2 Tablespoons of the Oil into a coverable sauté pan and heat over moderate flame. Fry Nigella Seeds for about 15 seconds, then stir in Onion mix. Fry stirring for a few minutes, then stir in Potatoes and 1 c Water. Cover and simmer until potatoes are nearly done, about 20 minutes.
10. Stir Cauliflower, Eggplant, Green Chilis and Salt (and a little water if it's too dry). Simmer, stirring a couple of times, for about 8 minutes until cauliflower is just crisp tender.
11. Adjust liquid if needed and taste for Salt. Stir in Fish and simmer covered just long enough for it to be hot.
12. Garnish with chopped Cilantro amd serve with plenty of steamed Basmati rice.