Dry roast all the ingredients under the section- "Dry roast and to be powdered" -- into a fine powder.
In a pan heat oil. Add mustard seeds, split bengal gram. Once the mustard seed stop splattering add shallot, curry leaves, garlic and sauté until the shallot turns translucent (golden brown).
Now add the tomato and sauté until it becomes mushy.
Now add brinjal, turmeric powder, 1/2 teaspoon (tsp.), sambar powder (optional) and sauté for 2 minutes.
After 2 minutes add little water, ground powder, salt as needed. Cover this and cook this until the brinjal is cooked. NOTE: time to time open the lid and stir the brinjal gently (so brinjal don't break) and also add little water if needed. Stirring is required to avoid burning.
Garnish with coriander leaves before remove from heat and serve.