As if butter wouldn’t melt As the cold spell this month has demonstrated, the frequently used cooking instruction “bring ingredient x to room temperature” can be quite useless.
Recipe writers sometimes give that instruction for meats, to take the chill off slightly before it’s cooked, although it isn’t absolutely necessary; if you ignore it, you might just leave the meat in the oven or on the fire for a little longer. More often, we’re told to do this when making baked goods. In countless cake and cookie recipes, we’re told to beat butter with sugar until the ingredients are light and fluffy. If you beat butter (and many other types of solid fat) straight out of the fridge, it stays waxy and hard, rather than combining easily with the other ingredients.
I was making a pound cake on the coldest day we’ve had this winter. As I’ve done so many other times, I took the butter out of the fridge and left it on the kitchen counter, so it would soften slightly. The fridge was four degrees Celsius, the kitchen was five degrees – so even after a couple of hours “at room temperature”, the butter had warmed up only one degree, which meant that it was still too firm.
I started making the cake anyway, hoping that by beating the butter for a long time in my heavy duty mixer, the friction would warm it sufficiently. It didn’t. After about 20 minutes of beating on medium-high speed, the consistency wasn’t right and the butter/sugar mixture was still dense and yellow, rather than being fluffy and pale.
In retrospect, I should have put the butter in another room, one that was heated. But by this point, I needed to get the cake in the oven quickly so grabbed my butane torch. I lit it and ran the fire around the exterior of the metal bowl. This sounds extreme but it works if you’re careful: you must avoid keeping the flame in one spot for more than a second, so the bowl becomes just slightly warm – I could put my hand on the metal without burning myself. As I did this, I could see the butter begin to soften, but, because I was working so carefully, it didn’t melt.
In Hong Kong, the problem with the kitchen being too cold isn’t something we have to deal with nearly as often as when it’s too warm. If you leave butter to come to room temperature when it’s 25 degrees or warmer outside, the fat will start to melt and separate – the oil will come to the surface, rather than remain cohesive. In this case, leave the butter at room temperature for no longer than 15 to 30 minutes – just so it softens slightly – when you press on it with your finger, it will yield gently. Don’t leave it out for too long, because once the butter starts to separate, there’s no going back. If this happens, use it for a dish in which you actually need melted butter, and start making the cookies or cake with another, slightly softened, block of butter.