Wash the beans well and soak in water overnight. Drain the beans. Bring 600 ml water, beans, turmeric and asafoetida to the boil in a pot. Stir occasionally. Simmer over medium heat without lid for 30-40 minutes until the beans are soft
Peel and finely dice the ginger. Heat the oil in a pan. Lightly sauté the ginger in it. Add coriander and cumin. Sweat while stirring constantly until it smells
Add spice mixture to the soup. Add a little more water as desired, season with salt and pepper. Wash the coriander and shake dry. Pluck off leaves and, except for a little garnish, chop finely and add to the soup. Fill soup into bowls and garnish with coriander leaves