and broken into quarters Salt and pepper Tarragon vinegar -=OR=Champagne vinegar (to taste) TIP STEM ENDS OF BEANS. Bring 4 litre water to boil and add 1.5 tablespoons salt. Cook beans in 2 batches until tender but still a little firm, then lift out. Lay them on a kitchen towel to dry for a minute or so. Transfer to a bowl. Add oils, shallot, tarragon and walnut pieces. Toss and season to taste with salt and pepper. Add a little vinegar just before serving. Serve warm.