For the bean patties, soak the beans in water for two hours.
Bring to a boil and simmer until the beans are soft.
Puree the beans with a hand blender.
Peel and finely chop the onion.
Mix the bean puree with the onion cubes, the egg and the tomato paste. Season with salt and pepper.
Heat oil in a pan and put a spoonful of the bean mixture.
Flatten a little and thus fry the bean pancakes one after the other on both sides.