Soak the lentils and beans for atleast 2 hours to overnight. Drain the water and keep ready.
In a pressure cooker, add the oil and heat at medium.
When the oil is hot, add mustard and cumin/fennel seeds and cover(the seeds will sputter out of the cooker).
Add in the curry leaves, asafetida(hing), coriander powder and green chili. Mix for a few seconds.
Add the ginger, garlic and shallots and cook for 2 minutes until shallots turn golden.
Add in the chopped tomato and turmeric powder and mix well. Cook for 3-4 minutes until tomato is mushy. This is the Tadka.
Add the drained and washed lentils+beans, water and salt and pressure cook on medium heat for 3-4 whistles. (20 minutes at with the pressure regulator at high pressure)
Let the pressure release by itself before opening. Serve hot topped with fresh cilantro.
To refresh the daal, add a fresh tadka/tempering. heat oil, add mustard and cumin seeds and some red pepper flakes and pour over the daal.
You can also pressure cook or slow cook the lentils till done and keep, and then add the tempering/tadka to it before serving, simmer for 10 minutes and serve.
To cook in a pan, use a deep pan with a lid and cook covered on medium heat for 15 minutes then low heat for 30 minutes or more until both the beans are tender.
Serve hot with Indian flat breads like Roti, Paratha , Naan, or with Rice or pilafs.