Peel and dice the onion and sauté in hot oil. Squeeze in the garlic and sauté briefly. Add the chopped tomatoes and the spices, stir everything well and let it simmer.
Put the beans in a colander, rinse well and drain. Pour into the hot tomato sauce, bring to the boil and season to taste.
Either serve the beans warm with tahini drizzled over them or cold, then pour the tahini over them just before serving.
When cooled, the beans are very suitable for a party, on the buffet or as a grill side dish. They can be prepared 1 to 2 days in advance.