Wash and rinse black lentils and red kidney beans in a large pot. Soak in 4 cups of warm water for at least 5 to 6 hours or overnight.
Before cooking, drain the water in which lentils were soaked, give a final rinse and transfer to a pressure cooker. Add garlic cloves, salt, olive oil and water and give it a stir.
Pressure cook on medium heat for about 8 to 10 whistles. Then cook for another 15 minutes on the lowest heat setting. Turn off the flame and let it release the pressure naturally.
In the mean time, prepare the tadka for the dal.
Heat olive oil and butter in a pan on medium heat. Add cumin seeds, coriander seeds, garlic and ginger. Sauté until fragrant and golden brown.
Add chopped onions and green chillies. Cook the onions for 6 to 8 minutes, until golden brown.
Add chopped tomatoes and cook for 3 to 4 minutes. Then add all the spices, i.e., salt, black pepper, red chilli powder, turmeric and garam masala. Mix to combine everything. Now, add tomato paste and keep stirring.
When the tomatoes start releasing oils from the sides, your tadka is ready. Keep aside.
Now, lift the whistle of the pressure cooker to check if all of the pressure is released. Open the pressure cooker. The lentils and kidney beans should be completely cooked and you should be able to mash them with your fingers very easily.
Turn on the heat on medium low and place the pressure cooker (without lid) on it. Add in the tadka. Mix everything using a ladle.
At this stage, do a taste test. Add more salt if needed. Also, add more water if the curry is too thick.
Let the lentil curry simmer with the tadka and spices for about 15-20 minutes. Stir occasionally. Add table cream. Simmer for 5 more minutes. Garnish with cilantro and table cream. Serve hot with garlic naan!