In large pot/ saucepan at medium heat, sauté in oil the onions, peppers and leeks till soft.
Add the curry powder and season, stir constantly till a rich deep colour is reached.
Add half the beans and simmer till soft, approx 1hr.
Check the seasoning and add the other half of the beans.
Chakalaka https://demandafrica.com/food/recipes/chakalaka/