In a large bowl or pot, add a good amount of ice and top with cold water. Add the quartered iceberg lettuce and submerge; this will rehydrate the lettuce and add a better crunch. The longer the lettuce has sat in the produce section, the more it loses its crisp texture, due to evaporation. Let the lettuce soak for 20 minutes or so. Then, using a salad spinner, dry the lettuce well.