garnish Shell peas and steam or parboil until tender. Douse immediately in cold water t o prevent overcooking, set aside to drain. (If frozen petite peas are substitut ed, cook two 10 ounce packages) Refrigerate all but one cup. Trim base of water cress stems and discard. Rinse bunch and pat dry. Melt butter in a large saucepan and saute onion until transparent. Add potato s lices, watercress, and basil. Pour in broth, and bring to a boil. Reduce heat, cover and cook until potatoes are tender about 10 minutes. Add peas. Remove fro m heat. In a food processor, puree this mixture in batches until smooth. Return puree t o saucepan and reheat slightly and season with salt and pepper to taste. Chill thoroughly. To serve, add cream, thinning soup to desired consistency. Stir in reserved pea s. Pour soup into serving bowls and crumble bacon over each. Add a dollop of so ur cream and top with a basil leaf.