Tech rundown: Heat gun
One of the fundamental skills of cooking is controlling the way that heat goes into (and, sometimes, comes out of) food. You can use a very gentle heat, like a controlled-temperature water bath, to warm the food slowly until the whole thing is the same temperature as the cooking medium. Or you can use a really high-heat source, like a blowtorch, to heat the outside of the food dramatically, while leaving the interior relatively untouched. This works well for crème brûlée because it allows you to melt and caramelize the sugar topping without curdling the custard. I’ve also used it to skin chillis while retaining their shape, a useful trick for making chiles rellenos.
Some techniques involve both approaches: In much sous vide meat cookery, for instance, a water bath brings the meat to temperature, while a very hot sauté pan or a blowtorch creates a crust on the outside. Even braises combine both approaches, browning the outside of the meat before simmering it gently until the collagen has all been rendered out.
I’ve recently started using a new-to-me source of heat, one that you may not have seen in the kitchen before, but that you may already have in your hardware toolbox: a heat gun. Essentially, a heat gun looks like a very powerful hairdryer, but one that gets so hot that you can use it to strip paint. (You do not want to point it at your head!) By blowing a directed stream of very hot air, it falls somewhere between an oven and a blowtorch: it gets hot enough to cause some serious chemical changes in food, but is relatively inefficient at delivering heat, so it gives you the ability to spread that heat around. My heat gun has “low” and “high” settings, but you can also control the heat by adjusting how close you hold it to the food. And the best part is that they’re not that expensive.
Originally, I bought the heat gun for confectionery use; it’s great for heating a mass of chocolate in short bursts, to keep it at the proper working temperature. If you tried that with a blowtorch, you’d get nothing but burnt chocolate. I also saw it used at Atelier’s el Bulli tribute dinner in place of a broiler, to melt cheese. And I recently used it to toast some walnuts. Normally, I would either dry-roast them in a skillet – an approach that often leads to uneven browning, especially if I get distracted – or toast them in the oven, which uses a lot of time and energy, since you have to heat the whole interior of the oven, rather than just the food. (Though, admittedly, I haven’t actually run the numbers to see if a heat gun is more efficient.)
Now that it’s at the front of my mind, I’m looking forward to seeing what other applications I can find for this tool. But if you’re still not convinced, I have a great “killer app” to share later in the week.