Many green beans are sold when they are small and do not need to have their strings removed. Older green beans and runner beans need stringing. To remove the strings, use a small sharp knife, cut each bean from the outer side across the stalk end towards the deeply grooved inner side. Stop just short of the edge and pull the string along the length of each bean. If the string breaks short, cut away a thin strip along the edge to remove it. Nick the top of the outer edge. If a string has been formed there, pull it out as well.
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