Cook the beans soaked overnight in 500 ml water, the onion peppered with a bay leaf and a clove, salt and vinegar for about 60 minutes over low heat. Drain the cooked beans in a colander.
Finely chop the chives and the other onion. Leave the diced bacon crispy in a pan and drain on kitchen paper. Mix the finely chopped onion, vegetable oil (I use olive oil), herb vinegar, chives, 2 small cress, a little sugar, salt and pepper to form a vinaigrette. Fold in the beans and add the bacon. Mix everything well.
The salad tastes lukewarm as well as cooled. Tastes very good when grilling.