Most people recoil at the thought of eating lard but it's been a useful ingredient since pigs were domesticated.
What is it? Fresh pork fat is sometimes called lard but the term usually refers to fat that's been rendered. Fresh pork fat is perishable, so rendering enables it to keep longer and makes it more versatile. Not all pork fat is equal: the best lard is white and firm, and is made from the back of the pig (called fatback) and the fat surrounding the kidneys. Other types of pork fat produce softer lard.
What to look for: check the label because most commercially made lard contains other ingredients to increase shelf life; it's also frequently hydrogenated. Homemade lard is best.
What else? Lard has a reputation for being high in cholesterol but it's actually better for you (or to be more accurate, less unhealthy) than hydrogenated vegetable shortenings.
How to use: first, you need to make it. The kidney fat might need to be ordered in advance as many butchers sell it to commercial manufacturers. Cut the fat into 1.5cm chunks and place in a heavy pan, preferably enamelled cast iron. Add water to a depth of about 1cm and cook over a very low heat until the fat renders out. This takes some time - don't try to hurry the process or the chunks will start to fry, which results in lard with a brown or golden tinge and a lower smoke-point (lard should be white). As the fat starts to render, the lard - a clear layer of liquid fat - will rise to the top. Stir the chunks of fat so they don't stick to the pan (if necessary, add a little more water). Ladle the liquid fat into sterilised jars; it will harden as it cools. Cover with plastic wrap and store in the fridge.
Good-quality lard makes the flakiest pastry, although its flavour is best appreciated in savoury preparations. If you want flakiness and flavour in sweet pastry dishes, use half lard and half butter.