Tip in all the five ingredients for the bhajja pitto (mixed roast powder) and stir continuously for 3 1/2 minutes (210 seconds). Switch off the heat.
As soon as it is cool enough, transfer to the dry grind jar of your food processor and grind to fine powder.
Store in a small, sun-dried, air-tight container or jar at room temperature.
Chop the brinjal to medium sized pieces of uniform size (see picture) and set aside.
Cut each grape tomato into 3 pieces and set aside.
Set a deep frying pan or wok on high heat. Pour in the cooking oil.
As soon as the oil is hot (it should not smoke), tip in a third of the brinjal pieces.
Stir occasionally and deep-fry for 10 minutes, or until the insides of the brinjal turn a golden brown. Lift out and drain off the excess oil.
Deep-fry the rest of the pieces likewise in two more batches.
Set a cast-iron wok (for best taste) on high heat. Pour in 50 ml of the flavorful hot oil in which you just deep-fried the brinjal. Throw in the mustard seeds.
As soon as the mustard seeds are about to finish crackling, pull the curry leaves off their sprigs and toss them in.
Stir once and tip in the tomato pieces. Stir and put in the powdered salt, the turmeric powder and the specified quantity of bhajja pitto. Stir for a minute.
Now chuck in the deep-fried brinjal pieces. Stir well for a minute more, and switch off the heat. Cover with a lid.
Your mouthwatering brinjal roast is now ready to enjoy! Serve with hot rice, porridge, cherupayar kanji, fried rice, biriyani, chappati, porotta, puri, pathiri, vellappam, idli, dosa, appo, machkat, or with freshly baked bread. Bon appétit!