braise onion in 4 tbsp oil til pinkish color add garlic, curry leaves, green chillies, fenugreek, cummin and mustard seeds let it splutter do stir
add tomato and saute add spices and salt and mix well
add potatoes and little water then cook till all most done add brinjals and simmer and when it dries a little keep off flame
garnish with chopped corriander leaves