Fill a large pot with water to a depth of 1 to 2 inches. Cover and bring to a boil. Uncover pot and arrange trimmed artichokes, bottoms up, in a single layer. Add stems around artichokes. Cover
pot, reduce heat to medium low and steam until tender, 20 to 40 minutes. Cooking time will vary greatly depending on the size of the artichokes. When the leaves pull out easily and the base can
be pierced with a knife, they're ready. Drain well and transfer to a large platter.