Pine nuts are tiny but their flavour is strong and distinctive.
What are they? Seeds harvested from the cones of certain types of pine tree. They're grown in Europe, parts of Asia (including Korea and China) and some areas of North America. The thin, brittle, easy-to-crack brown shell hides a small ivory-coloured nut that's high in fat and slightly waxy in texture when raw. They have a rich, buttery, slightly sweet flavour.
Where to buy: not in upmarket supermarkets, where small packs of imported pine nuts are outrageously expensive. Chinese food shops sell the shelled nuts at a fair price, as do vendors in South Korea. If possible, buy the (relatively) large nuts rather than tiny ones. Don't bother buying unshelled nuts, even though they're much cheaper, because it takes a long time to shell enough for a recipe.
What else? If a recipe calls for pine nuts, it always means the shelled variety - don't make the mistake of using the whole (unshelled) seeds because they'll make your dish unpleasantly crunchy and basically inedible (yes, this is speaking from experience). Because pine nuts are high in fat, they turn rancid quickly, so wrap them tightly in plastic wrap and store in the freezer. Pine nuts have more flavour when toasted, which can be done in an unoiled skillet on the stovetop (stir them constantly because they burn easily) or in the oven until they're fragrant and light brown. Let them cool before using.
How to use: they're essential in a traditional pesto, made by pounding fresh basil leaves with olive oil, garlic, salt, cheese and pine nuts. Toasted nuts add crunch and flavour to simple salads, pasta dishes, sauces and dips. Pine nuts are also used in sweet dishes. You can use them instead of other types of nut in biscuits, but if you really want to showcase nuts, make pine nut-almond macaroons by beating almond paste with egg whites, sugar and flour. Shape the dough into small balls and roll them in raw (untoasted) pine nuts, pressing so they adhere. Set the balls on an aluminium-lined baking tray, leaving room for them to spread slightly, then bake until the biscuits are firm and fragrant. If you have a heavy-duty mixer, you can make pine-nut nougat by beating egg whites with boiling hot honey-based syrup until cool and thick. Stir in toasted pine nuts then use a lightly oiled spatula to press the mixture onto a baking tray lined with edible rice-paper wafers.