Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
   1       Head         lettuce
   2       cup          Vinegar
   1       cup          Water
   3       Teaspoon     Salt
   2       Teaspoon     Dill weed or dill seed
   2       Teaspoon     Fennel, fresh or seed
   1       Tablespoon   Rue (optional)

Preparation:

1) Combine the water and salt in a 1-quart jar which has a tight fitting lid. Add the vinegar, dill, fennel, and rue. 2) Separate the lettuce leaves and add them to the liquid. Seal the jar and let sit until ready (about 48 hours) NOTE: The original recipe from Columella calls for salting the lettuce first, letting it "sweat" for 24 hours, and then pickling.