Old-fashioned “pottage” seems the right name for this essence-of-spring soup. Why bother to gussy up a good thing, when the time-honored basic works so well? Although the spruce hue and lush body suggest intensity, the soup is surprisingly light in flavor and feel. Stir in cream, if you prefer a richer effect.
Double the quantity of nettles if you want to use just one green. For tangy depth, add wild dock or sorrel; for satiny smoothness and shine, add mallows. Whatever you choose, figure on a total of 2 quarts lightly packed trimmed leaves.