Wash dry Chickpea Lentils/Bengal gram (chana dal) for 3-4 times, until the water run clear through the lentils. Soak it for 6-8 hours.
Right before processing the lentils, Start your food steamer by placing water at the bottom and greased thali/tray on a stand inside the steamer. This will assure the thai/tray to be hot with boiling water once we are ready with the batter.
After 6-8 hours of soaking, remove all the water from the lentils. Place soaked lentils in a food processor with 6 thai green chili, 3 large garlic cloves and 2 inch ginger root.
Start processing it, use as little water as possible. Add ¼ cup at a time to process it to grainy texture while keeping it thick. You should not need more than ½ to ¾ cup of water.
Once processed, take it out in a big wide bowl. Add in 2 tbsp of sugar, 2 tbsp of lime juice, ¼ tsp of asafetida (hing), ¼ tsp of turmeric powder, 2 tsp salt. Mix it vigorously using a whisker for 3-4 minutes. It will start to become light and fluffy. Add little water at a time if the batter is too thick, and keep whisking it continuously.
Once the batter become light and has thick runny consistency, add in 1 tsp of eno (fruit salt), and whisk again vigorously in just one direction.
As soon as the batter is fully fluffy with eno (fruit salt), immediately pour it out in a greased hot steam thali/tray. Cover the steamer and steam it for 20 minutes. Once steamed, poke it with a knife to assure steaming all the way through the batter. If the batter does not stick to the knife, that means it is fully steamed.
Once steamed, take the thali/tray out of the steamer and let it cool down for 15-20 minutes or so. This is called khaman.