A recipe typical of the Vaucluse and Ardêche country, the area west of the Rhône valley stretching from Avignon to Lyons. The mixture may also be poured into a fat-lined terrine, baked for 1½ hours in a 350° oven, and cooled under weight. It becomes la terrine aux herbes, a specialty of Chez-Hiély-Lucullus in Avignon, one of the finest restaurants in France for the appreciation of regional cooking (and, among restaurants of quality, probably the least expensive).
The spinach is sometimes replaced, in part, by the green parts of the leaves of Swiss chard, also parboiled (10 minutes), pressed, and chopped. Caul (crêpine) is the thin, fatty, weblike membrane surrounding the pig’s intestines. You may have to go to a specialty pork butcher for it or ask your butcher to order it especially. If you cannot find caul, substitute a couple of thin strips of fatback or bacon, wrapping each caillette so that they cross on the top surface, the ends being tucked beneath.
Caillettes are nearly always eaten cold as a first course, but, traditionally, they are served hot at Christmastime, accompanied by a truffle sauce.