If you do not have a terrine mold, the bottom of a loaf pan may be lined with one long strip of fat, and the sides left bare.
To line a terrine mold: cut barding fat to fit the sides of the mold and line the mold with it. If serving the terrine unmolded, for attractive effect put a bay leaf and herbs at the bottom of the mold then cut strips of fat and arrange them in a lattice pattern on top of them.
Add the terrine mixture.
Seal the gap between the lid and rim of the mold with luting paste to keep in most of the steam. Roll the paste into a rope and insert it into the gap around the lid.
Cook in a water bath. Cool until the terrine is tepid. Remove the Iid and set a 1 Ib/500 g weight on top so the mixture is compressed and slices well. Refrigerate until cold and unmold for serving.