Chilled Sorrel and Herb Soup with Tomato Cream

This recipe is a version of the summer soups common to nineteenth-century Europe and America. Called green soup or garden soup, they used whatever greens and herbs were in the garden: lettuces, endives, sorrel, herbs (including parsley and lovage), vegetable tops, watercress, etc. Water as the base will give a purer, truer taste of the greens themselves, but a light chicken stock will make it richer. I prefer water.