Cut onions and brinjals into semi-circular pieces. Heat the oil. Add mustard seeds. When it splutters, add the urad dal. When the urad dal is roasted, add the onions and brinjals. Add salt and red chilli powder. Fry with constant stirring until the brinjals and onions become soft. Instead of the red chilly powder,you may try it out with paruuppu podi or the normal molagai podi. It tastes really good with paruppu podi