Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
   2      cans          tuna in oil
   9                    leaves gelatin -- or 9 tablespoons
   1      cup           mayonnaise
   1                    onion
   1      teaspoon      mustard
   1      teaspoon      Worcestershire sauce
     1/2  cup           heavy cream
   2      tablespoons   capers
   2      cups          gherkins -- chopped
                        pepper -- ground
                        oil
     1/2  cup           water
   1      cup           fish stock

Preparation:

Process tuna and onion in food processor. Add capers, Worcestershire and mustard. Dissolve 6 of the gelatin leaves in warm water. Let cool and add to processor. Process to blend. Add cream and mayo and process to blend. Dissolve rest of gelatin in 1 cup fish stock. Let cool. Stir in gherkins. Oil a mold and pour gelatin with gherkins. Let set in refrigerator. Pour tuna on top. Chill until set. Unmold by dipping mold in warm water bed for 15 seconds. Surround mousse with shredded lettuce.