Many years ago, we invited a bunch of people for lunch two days after Christmas, to use up the leftovers from an enormous holiday dinner party. We had just found a great soup recipe that we thought would be a perfect addition to the leftover casserole. We added a crisp salad with a light dressing, and it was a great meal. The casserole comes from an old edition of 'The Joy of Cooking', and uses leftover turkey. This was also a 'food memory' from a visit with a friend who invited me to lunch after a Thanksgiving. The soup is...