For dumplings, sift the chickpea (gram) flour into a large bowl. Add chili powder, 1/2 tsp salt, baking soda, onion, green chiles, and cilantro. Mix. Add water and form a thick paste. Heat the oil in a skillet. Put teaspoonfuls of the paste in the oil and cook over medium heat, turning once, until crisp golden brown. Set aside.
For yogurt sauce, put yogurt in a bowl and whisk with the gram flour and water. Add all spices and 11/2 tsp salt. Mix well.
Press mixture through a large strainer into a pan. Bring to a boil on low heat, stirring constantly. If it becomes too thick, add water.
Pour the sauce into a depp serving dish and arrange all the dumplings on top. Set aside but keep warm.
For dressing, heat the oil in a skillet. Add the cumin seeds and chiles and fry until darker in color and giving off an aroma. Pour the dressing over the dumplings and serve hot.