No huge secret here: the answer lies in temperature and cooking time

I prefer meringues with a chewy centre, but mine are often too dried out. How can I ensure chewy ones?
Karen, Glasgow

As we’ve noted before, baking is the most precise of all culinary endeavours, but that doesn’t really apply to meringues. There are almost as many ways to make meringues as there are dishes that feature them.

But, first off, there may be a very simple solution to your predicament. Most of us tend implicitly to trust our oven settings, but the temperatures in domestic ovens vary much more than we’re led to believe – just because you’ve turned that knob to, say, 120C/250F, doesn’t mean the oven is actually at 120C. (On top of which, the heat isn’t consistent, either, with variations from top to bottom, front to back and side to side.) And that can make a world of difference with meringues, which need baking at low temperatures – 93C, ideally, according to kitchen geek supreme Harold McGee in his landmark 2004 book On Food and Cooking: An Encyclopedia of Kitchen Science, History and Culture, which devotes all of five pages to the subject. Even so, that’s perhaps a tad too precise for the domestic kitchen – I don’t know about you, but the temperature gauge on my cooker isn’t anywhere near that exact – which is where an oven thermometer comes in handy. This isn’t your typical piece of expensive kitchen kit that you use once before sticking in the back of the cupboard; you can pick one up for as little as £5, and it’ll help you keep on top of what’s going on in that hot, dark place (I’m assuming that you, too, haven’t yet got round to replacing that blown oven bulb).

That said, not everyone agrees with McGee where temperature is concerned. Former Guardian baking columnist Dan Lepard, among many, many others, goes for an hour and a half to two hours at 120C (100C fan)/gas ¼, while Feast’s own Yotam Ottolenghi gives his meringues a short, sharp shock: “The old trick of whisking in a dash of vinegar and a little cornflour once the meringue is nice and airy always does the trick, and helps give the meringue a short, brittle texture on the outside. I heat the oven to relatively high, then turn it right down as soon as the meringue is in, so it puffs up.” As Lepard says, “You are not so much cooking meringue as drying it out, so there’s no great mystery to a chewy one: just cook it for less time than you normally do.”

The type of sugar you use, and when you put it in, are also factors. “If the sugar is added after the egg whites have been whipped, the meringue will be relatively light,” McGee writes, whereas mixing it in earlier leads to a denser end result. Lepard urges you to add it gradually, “just a few spoonfuls at a time, to make sure the foam stays as light and aerated as possible”. Also, granulated sugar doesn’t dissolve sufficiently at such low temperatures, leaving what McGee calls “weeping sugar drops” in the finished meringue, which is why professional bakers prefer caster, a mix of caster and icing, or even sugar syrup, to guarantee consistency. (The standard ratio is two parts sugar to one part egg white by weight.)

The temperature of the whites is important, too. Lepard leaves his out overnight, to make them easier to whip, adding that “you’ll get more volume this way”. In his book Short & Sweet, he recommends using a machine to whisk the whites, in part to save on elbow grease, but mainly to ensure they’re whipped to the required consistency, namely “very thick, smooth and glossy”. How you cook them after that, however, is up to personal taste. “Just be sure to bake them just until the middle is set and chewy – no more – to get that perfect, nougat-like texture.”