Put the dal and 4 cups of water in a heavy 3-qt pot. Bring to boil and skim off the scum. Add ginger and turmeric. Turn low and cover in such a way as to leave the lid slightly ajar. Cook for 1 to 1 1/2 hours till dal is no longer grainy. When done, a thick puree settles to the bottom and a thin "dal water" rises to the top. Turn the heat very low if necessary to avoid sticking, esp during the last 15 minutes. Add the salt and mix it in. Keep the dal covered and hot.

Heat the oil in a small skillet over medium heat. When hot, put in the asefetida, then the cumin and hot peppers. This should take about 10 seconds total. Quickly pour the oil and spices into the hot dal. Cover it immediately and let it absorb the flavorings for at least one minute before serving.