Cut off the top of the artichoke with a knife and trim the sharp points of the leaves with scissors, rubbing with cut lemon as you go to avoid discoloration
Remove the choke and squeeze with lemon juice
Place artichokes in a large steamer or pot of boiling water until heart is tender, about 20 minutes depending upon size
Allow to cool
Brush both sides of the artichoke with the butter mixture, grill until until golden on the surface and heated through, about 5 to 10 minutes