There are two things you must have to hand when preparing artichokes: a really sharp paring knife and a supply of halved lemons. The dark green, inedible parts of an artichoke are notoriously tough, and any cut surfaces will oxidise or blacken within a minute unless rubbed with lemon.
The simplest way to cook and eat an artichoke is to boil it in salted water containing a couple of lemon halves until the tip of a knife finds the heart or base to be tender (I don’t like to cook them in anything other than stainless steel pans). First trim the tips of the petals by about a third and rub with lemon, then remove the first outer layer or so of the outer petals. Cut off the stem and carefully trim the remaining dark green bits from the base of the artichoke. Rub with lemon and put it in the saucepan. After cooking, open out the top of the artichoke and remove all of the hairy choke with a teaspoon (I use a worn, and thus sharp, one). To eat the artichoke, remove the leaves, each with a nugget of edible heart attached, and nibble this off until all that is left is the prize – the heart. Use a classic vinaigrette as a dip or sauce.