Cooked artichokes yield tender stems, hearts and leaf bases if they are cooked for the right length of time and until they are tender. It's sometimes difficult to judge if the artichokes are done cooking, because the outer leaves remain tough and fibrous. Cooking time depends on the size of the artichokes and method used, but judging doneness is similar, no matter how you cook the artichokes.
Boiled artichokes take 20 to 40 minutes to cook, depending on the quantity and size of the artichokes. Once cleaned and trimmed, submerge whole artichokes in boiling water and cook them until tender. Artichokes tend to float when boiled, which results in slower cooking or uneven cooking. Setting a plate or pot weight on top of them as they boil keeps them covered. To check for doneness, lift an artichoke from the water with tongs and try to pierce the bottom of the stem with a skewer. If it penetrates easily, the artichokes are cooked.
Steamed artichokes take around 45 minutes, but the process results in tender, deep green vegetables that aren't watery or mushy. The artichokes are held above 1 to 2 inches of boiling water in a steamer basket throughout the cooking process. Their color brightens the closer they are to being done. Just like boiled artichokes, using a skewer to check tenderness provides the best guide to determine if they are done.
You can prepare artichoke hearts by cooking the whole artichoke by boiling or steaming, then cutting out the heart, or by removing the leaves and only cooking the heart and stem by boiling or steaming. If you first prepare the whole artichoke, use the same times and tenderness checking methods as you would for serving a whole artichoke. The hearts cook more quickly if you remove the leaves first, and can finish cooking within 20 to 30 minutes using either method.
Removing the fibrous, inedible choke first can help speed cooking and shave 10 minutes off the cooking time. Trim off the top of the artichoke, the bottom of the stem, and snip off the pointed tips of each leaf. Slice the artichoke in half and scoop out the choke with a melon baller before boiling or steaming. If you want to serve whole artichokes, use a small melon baller to scoop the choke out from the bottom center of the stem. The choke is tough and sometimes difficult to remove before cooking, but it scoops out easily if you cook the artichokes until they are done.