Let the yogurt sit for 24 hours at room temperature so that it has a slightly sour taste. Wash the dal thoroughly. Place the dal, 3 cups water, a pinch of turmeric and 1/2 tsp salt in a saucepan and bring to a boil. Lower the heat, cover loosely, and simmer until the dal has split open but is still whole. (It should not become mushy.) Drain and put aside. Whisk together the yogurt, 3 3/4 cups water and gram flour. [Add the water gradually, and quit when a good-looking consistency is reached.] Grind two of the chilies and the ginger to a paste. Heat the ghee in a large saucepan. Add the remaining two chilies, broken in half, cinnamon, cumin, and hing and let them sizzle for 5 or 6 seconds. Add the yogurt mixture, the remaining turmeric and salt, sugar and the chili and ginger paste. Stirring constantly, cook for 5 to 7 minutes. Add the drained dal and cook for a further 5 minutes until thick. Garnish with the chopped cilantro leaves. Indian Regional Cooking; Sumana Ray