White Bean Salad with Tomatoes
Cook the beans in a pot of boiling salted water until tender, about 25-30 minutes.
Drain and allow to cool.
Rinse the tomatoes and cut into wedges. Rinse the cucumbers, peel, halve lengthwise and slice. Rinse the fennel and cut into thin strips. Rinse the watercress.
Peel and dice the onion.
In a bowl, stir the onions with the vinegar, and season with salt and pepper to taste, and the sugar. Whisk the yolk into the vinegar mixture while gradually adding the oil. In a bowl, stir the beans with the tomato, cucumber, fennel and dressing until thoroughly combined. Stir in the watercress and serve immediately.