Soak the hurali, moong, peanuts and chana overnight.
Boil them in a pressure cooker. Note: Hurali usually takes much longer than other dals.
Put everything in a big vessel. Add salt and boil for 5 minutes. Add about 3 - 4 cups of water. Boil together for a few more minutes, stirring often.
Strain the beans and set them aside. The remaining liquid is the Kattu.
Roast the coriander seeds, methi and cumin seeds together. Dry grind them and add to the kattu with a little salt.
In a pan, heat about 2 tablespoons of oil. Add mustard. After the mustard pops, add curry leaves. Add the seasoning to the kalu.
Serve the Kalu and the Kattu separately.
Notes
The one ingredient you cannot substitute is Hurali, because of its distinctive taste. It is also known as Horse gram and is available in many Indian stores. It is a small, round, flat, bean with a medium brown color.