1. Wash artichokes under cold running water.
2. Pull off lower petals which are small or discolored.
3. Cut stems close to base. (Use stainless knives to prevent discoloration.)
4. Cut off top quarter and tips of petals, if desired. (Generally, some people like the look of clipped petals, but it really isn't necessary to remove the thorns. They soften with cooking and pose no threat to diners.)
5. 5. Plunge into acidified water to preserve color. (One tablespoon vinegar or lemon juice per quart of water.)