Soak the kidney beans for 6-8 hours in plenty water, best to soak them overnight. Discard the soaking water and add in a pot the kidney beans, 1¼ liter water, the peel of the ginger, the bay leaf and the cinnamon stick. Bring to a boil and cook for 10 minutes at high heat to kill the toxins. Reduce the heat to low and simmer for another 10 minutes or until the beans are soft.
Mix the 20g ginger and 20g garlic with 1 tablespoon oil in a small blender. Peel the onion and chop finely. Cut the tomatoes in four and remove the seeds. Mix the tomatoes in a blender, you need at least 350ml tomato puree.
Bring a wok or indian kadai to medium heat and add the ghee. Add the onions and cook until they start browning 8-10 minutes. Add the ginger and garlic paste and continue cooking until they loose their rawness.
Add the coriander powder, chilli powder, turmeric powder and cumin powder. Cook for another 2 minutes and add the tomato paste and tomato puree. Season with salt and cook at medium heat for about 10 minutes.
Add the cooked beans and 500ml of the cooking water. Add the garam masala and cook for another 10 minutes to bring it all together.
Transfer the Rajma in a large serving bowl. You can decorate the rajma with red onions and fresh coriander. Serve with steamed rice and yoghurt.