Wash and soak Horse gram along with Black chickpeas, Channa dal and Brown rice over night. Dry roast the oats and powder it. keep aside. Now grind all the soaked ingredients along with curry leaves, ginger, garlic, pepper corns and dry red chilli.
Grind it coarsely by adding water little by little. The consistency of the batter should not be too thin.
Add salt and drumstick leaves to the batter. Mix well. Heat a non stick tawa, pour one ladle of batter and prepare like dosa.
Smear very little amount of olive oil and cook both the sides in a lower flame, till the adai turns crispy.
Once done, remove from the flame and repeat the process for the remaining batter.
Serve hot with Roasted gram chutney or Tomato Chutney or any chutney.