Prep the Dals: Sort, wash, and drain the moong and urad dals.
Then, in a large bowl, soak all three dals in 3 cups / 710 ml of hot water for 3–5 hours.
After soaking, rinse well and drain completely. 2.
Cook the Dals: Place the drained dals, 7 cups (1680 ml) / 1. 75 liters of fresh water, turmeric, and a dab of the ghee or oil in a heavy 3-quart/liter saucepan.
Stirring occasionally, bring to a full boil over high heat.
Reduce the heat to moderately low, cover with a tight-fitting lid, and simmer gently for 1½ hours, or until the dals are soft and fully cooked.
Stir occasionally to prevent sticking. 3.
Finish the Dal Base: Remove the pot from the heat.
Add the salt and beat with a wire whisk or an immersion blender until the dal is creamy and smooth. 4. Make the Tadka (Tempering): Combine the cumin, coriander, fennel seeds, and red chilies in a small bowl.
Heat the remaining ghee or oil in a small saucepan over moderately high heat.
When it is hot, add the seed mixture and stir-fry until the seeds are fragrant and turn a rich brown color. 5.
Combine and Serve: Quickly stir the asafetida powder and the cassia or bay leaf into the hot spices, then immediately pour the sizzling tadka into the cooked dal.
Cover the pot at once and let the seasonings infuse for 1–2 minutes. Uncover, garnish with the minced parsley or coriander, stir, and serve hot.
Don't skip the soak. Soaking the dals not only speeds up cooking time but also makes them easier to digest.