Remove leaves from lettuce stems. Choose a few handfuls of the smallest ones; rinse, spin-dry, then chill. Refrigerate remaining leaves for another use. Pare off all fibrous pale (and bitter) peel from stems. Cut stems crosswise into 4-inch-thick slices (about 2 cups).
Nip off enough cilantro leaves to make ¼ cup, very tightly packed. Rinse and spin-dry. Slice