For a richer sauce, you can substitute half of the buttermilk with thick yogurt.
If you don't have a steamer, you can place the koftas on a plate covered with foil and place it in a pot with boiling water, covering the pot to steam.
Roasting the channa dal before grinding enhances the nutty flavor of the sauce significantly.
Be careful not to boil the buttermilk sauce vigorously, as it may split. Keep the heat low to medium.
Leftovers can be stored in an airtight container in the refrigerator for up to 2 days. Reheat gently on the stove.