Place the brinjals on the microwave turnable and microwave on high for 5 minutes. De-skin the brinjals and keep the pulp aside.
Combine the oil, onions, green chillies and ginger in a microwave-proof bowl and microwave on high for 6 minutes stirring once in between after 3 minutes.
Add the brinjal pulp, coriander powder, chilli powder, turmeric powder and salt, mix well and microwave on high for 2 minutes.
Add the garam masala, tomato purée and tomatoes, mix well and microwave on high for 3 minutes.
Serve hot.