Chilled wax beans paired with fresh chervil make a refreshing salad. Arrange the beans around a glass plate with their pointed tails outward to create a striking visual effect.
1. Rinse and trim the beans, but leave the pointed tails intact. Drop them into a large pot of boiling, salted water and cook, uncovered, at a gentle bubble for 6 to 8 minutes or until crisp-tender. Drain in a colander set under cold running water. Drain thoroughly and transfer to a large bowl. Sprinkle on the onions and toss to combine.
2. In a small bowl, whisk together the oil, vinegar, salt, and cayenne. Pout over the beans and toss to coat. Cover the bowl and refrigerate, stirring occasionally, to ensure even marinating.
3. When thoroughly chilled, arrange the beans on a glass plate, sprinkle with chervil, and pour on the dressing that remains in the bowl. Chill briefly or serve at once.