Cut eggplants in 1/2" thick round shape pieces. Now wash all pieces and keep it in a strainer.
Put pieces in a big bowl then sprinkle 3/4 tsp salt on it. Keep aside for five minutes.
Heat 1/2 oil in a heavy bottom pan on high heat then reduce heat on medium. Put some pieces in oil and fry both sides till golden brown colour. Heat rest of oil and repeat the same thing to rest of pieces. Keep them in a plate.
Take curd and sugar in a big bowl. Stir continuously till it turns smooth and lumps free consistency. Now add salt, black salt, cumin - chilly powder and stir well. Add half cup water to make little thin consistency.
Drop fried eggplant pieces in curd and mix very gently.
Heat oil in a pan / kadai. Put chilly, mustard seeds, curry leaves and fry for a minute.
Add chopped garlic, onion, a pinch of salt and fry till pink colour. Put it in curd and stir gently so that all flavor will mix together.
