Artichoke bases are prepared by breaking off the stem of the artichoke by bending it until it comes off the base. Cut the base flat and then remove the leaves. Trim the outside of the heart and then remove the choke, being certain to remove all last traces. Rub the heart with lemon to prevent it from discolouring. These are sometimes referred to as artichoke hearts, that are from young artichokes in which the bracts have not yet formed the choke and are included with the base.