Kevin Schofield's writings, observations, and other pointless distractions
In my last year at Microsoft Research, I developed a reputation for bringing cupcakes into the office. This was something of a labor of love for me: I enjoy cooking and baking, and while I’m not particularly artistic, I think I do have a pretty good sense of flavor. A few years back I took a series of classes on cake-making that was taught by a professional wedding-cake maker, and it helped immensely in my ability to turn out awesome tasting cake and frosting.
People ask me regularly about how I make the cupcakes. In truth, there is no great secret. Or if there was, it won’t be by the time I’m done writing this, as I’m about to “tell all” on how I make them.
Let’s start with the cake, and some blasphemy. While cake made from scratch is really amazing and I enjoy doing that, I often don’t have the time. It turns out that many of the techniques you use to make cake from scratch can be applied to cake from a box mix, and the vast majority of people can’t tell the difference in the end result. So rather than try to explain how to make cake from scratch, let me just tell you how you can use a box mix to achieve nearly the same thing and save yourself a ton of time.
There are several things you have to get right (and again, most of these apply equally to from-scratch or from-a-box).
1. Sift the mix — or more generally, all the dry ingredients. This ensures that you have regular consistency, and no big lumps that won’t mix evenly. Also, if you’re using a box mix, you’ll discover when you sift it that there’s some, uh, “stuff” left over that is unrecognizable — throw it away, because you don’t want that in your cake batter. Different box mixes have different amounts of “stuff,” and I recommend Duncan Hines Classic mixes (devil’s food, yellow, and white) for having the least amount in my personal experience (plus they are often on sale at my local grocery store and I can stock up ahead of time).
2. Bring all ingredients, including the eggs, up to room temperature first before you start making the batter. This is a general rule for cooking, but it’s very important for something as carefully timed as baking. Using cold eggs doesn’t itself change the taste or consistency of the cake, but it increases the amount of time it needs to cook, and since it takes time for the heat to penetrate all the way through to the center of the cake, it may cause the parts nearer the outside to be drier than the inside. As an aside: in the United States we’re weird about our eggs: we buy large amounts of them at once then refrigerate them. In many other parts of the world, people buy fewer eggs at once, and leave them at room temperature; eggs are just fine for a few days without being refrigerated. In my experience, it will take about 30 minutes for eggs to come up to room temperature after removing them from the refrigerator, but if you know in advance that you’ll be needing them, you can take them out hours ahead of time and save yourself the hassle. If you forget or are being spontaneous (both of which often happen in my cooking adventures), then you can bring eggs reasonably close to room temperature in about 10 minutes by immersing them in a bowl of lukewarm water — though make sure it’s lukewarm, NOT hot! You don’t want to cook the eggs, just take the chill off.
3. Mix all the dry ingredients together in one bowl, and all the wet ingredients in another bowl, before you try to mix them together. Again, this is a handy general cooking tip. The goal here is to get ingredients consistently dispersed through your creation; we’ve all had the experience at one time or another of having some amazing dish where one bite was particularly salty, or spicy, because it wasn’t thoroughly mixed. It’s so much easier to mix dry ingredients all together, and wet ingredients all together, before you combine them. Once you start doing this and realize how much of a difference it makes, you’ll never go back. Eggs in particular are nice to mix ahead of time with the wet ingredients, because they tend to stay clumpy; it takes about 30 seconds of energetic mixing for the clumpiness to break down. You can tell you’ve mixed them enough because if you lift your fork or whisk out of the bowl, the eggs will smoothly flow down back into the bowl without any clumps.
4. Preheat your oven. This means two things. First: you need to ensure that your oven is preheated to the right temperature — and the built-in thermostats in most ovens are wrong, by as much as 20 degrees. Don’t think this is just a problem with old ovens; a few years back I remodeled my kitchen and put in a new expensive oven, and sure enough, the thermostat was off by almost 20 degrees. Fortunately, many ovens allow you to calibrate the thermostat (look in the user’s manual). So: go buy an oven thermometer, stick it in your oven, and leave it there. There are good ones that are ridiculously cheap, and it will make a huge difference in your cooking.
Second: after your oven reaches the desired temperature, wait another ten minutes before you start baking. The thermometer is telling you that the air in your oven is that temperature, but that doesn’t mean that the walls of your oven are the right temperature yet, and the walls are critically important in maintaining an even and steady temperature. When you open the oven door to insert your cupcakes, some of the hot air rushes out and your oven temperature can drop dramatically. When the walls are hot, then they help bring the new air up to the desired temperature much faster; warm walls also help to ensure a more consistent temperature throughout the oven. And one more thing: if you do re-calibrate your oven, match it to the oven thermometer temperature after it’s been sitting at temperature for ten minutes, because you don’t know where the thermostat is within the oven: it could be registering the wall temperature more than the air temperature.
5.Bake your cupcakes until they are done. Ignore the timing guidelines on the box; they were written knowing that people use cold ingredients and under-heated ovens, to encourage erring on the side of over-cooking. The Duncan Hines classic devil’s food box recipe calls for baking cupcakes for 18-22 minutes; in my kitchen, my cupcakes are consistently done in 16. Two minutes can make a big difference: if I left them in until 18 minutes, they would already have started to dry out. That is another advantage of doing all the steps above: your baking becomes extremely predictable.
There is a very simple test for whether your cupcakes are done: tap them on the top. If they bounce back, they are done. If tapping leaves an indentation, they still need to bake more. Tap a few of them at different positions in the cupcake pan, since your oven may have cooler spots. Also think about rotating the pans halfway through the expected coking time to minimize the differences across the batch.
So now you have cakes, and you need frosting. Unlike the cake, I always make the frosting from scratch; I haven’t found any particularly satisfying alternative. There are dozens of variations of frosting, but my favorite is Swiss Butter Cream. Below is the recipe I use. Arguably, all the time I save on the cakes gets invested into the frosting, but it’s so worth it. I will warn you that this is a recipe that you will get the “feel” for after doing it a few times when you know what to expect and what tolerances you have; it’s far less predictable than the cake and requires tasting and testing as you go along. Also, I highly recommend a stand mixer (e.g. KitchenAid) for this recipe; if you don’t have one, borrow one from a friend. I’m not suggesting you can’t do it with a hand mixer, but it would be harder and you might not be happy with the results.
A note on vanilla extract: while regular, natural vanilla extract is brown, we would only want to use that if we were making a brown or otherwise dark-colored frosting (e.g. chocolate, coffee, mocha, etc.) since the vanilla extract would otherwise discolor it. However, you can buy clear vanilla extract for just these purposes. It’s imitation, but it works just fine.
Cut the butter into 1/2 inch cubes. It’s easier to cube it when it’s cold straight from the refrigerator, then set aside and let it come up to room temperature.
Put the egg whites and the sugar in the upper part of a double boiler. I create a make-shift double boiler by putting the egg whites and sugar into the mixing bowl, and resting that on top of a large pot with about an inch of water in the bottom.
This has the added convenience of letting me move the egg white/sugar mixture (aka “meringue”) straight to the mixer when it’s finished on the stove. But I’m getting ahead of myself…
When the water is boiling, place the container with the egg white/sugar mixture on top and whisk it constantly until the mixture reaches 110 degrees F. (yes, this involves stopping whisking from time and sticking a thermometer into the mix – do this quickly) We heat it like this for two reasons: it kills bacteria that might be in the egg, and it causes the sugar to fully dissolve so that the result is very smooth rather than grainy. Be sure not to overheat it, as the egg will start to cook.
When done whisking and the egg white mixture is at the right temperature, move it to the mixer and use the whisk blade to whisk it at high speed for several minutes until it has hard peaks.
(What is a hard peak? Stick a utensil or the mixer blade into the meringue, pull it out and turn it up towards the ceiling. If the meringue points to the ceiling, it’s a hard peak. If it curls over, it’s a “soft peak” and it needs more whisking)
Switch out the whisk blade for the beater blade. Start the mixer on low, and slowly add in the butter, 5 or 6 cubes at a time, allowing the butter to incorporate into the mix before adding more. When it’s all incorporated, beat the mixture on high speed until it whips up into a smooth, silky frosting that’s firm enough to hold its shape. A couple of important notes: first, you’ll probably want to throw a dish towel over your mixer while this is going on, as it tends to spit bits of frosting out of the bowl from time to time. Second, at some point during this process the mix will look like it’s curdled and you won’t believe that it could ever turn into beautiful frosting. Have faith and just keep the mixer going, and a few minutes later you will be rewarded.
At this point, you have a bowl of gorgeous white frosting that tastes sickly sweet and buttery (go ahead, taste it — we’re about to fix it and you’ll want to know what it was like before). The next step is to “balance” the frosting; the point here is to bring it back to a neutral place so that the sweetness and butter doesn’t overwhelm the flavor we want it to have. There’s no easy way to describe this in words, but you’ll know it when you taste it. In a small prep bowl, mix together 1/2 teaspoon of lemon juice, 1/2 teaspoon of vanilla extract, and 1/4 teaspoon of kosher salt until the salt is fully dissolved. Make sure to taste the frosting as it exists now, before we start balancing it. Now add the lemon/vanilla/salt into the mixing bowl with the frosting, and mix on low speed for 30 seconds to incorporate it into the frosting. Taste it again — isn’t that cool? From here, add small increments of salt, lemon juice and/or vanilla until you’ve found a satisfying neutral point. Dissolve the salt before you add it into the frosting, so it doesn’t end up being undissolved grains mixed in. If you are very consistent with using the same ingredients (including always buying the same kind of unsalted butter) you will find that you will get very good at adding the right amount of lemon, vanilla and salt the first time, and you will cut down substantially on the number of iterations required to balance you frosting.
At this point you can add the desired flavoring. The only trick here is to minimize the additional amount of liquid you add, because at some point you will start thinning out the frosting. I often use pureed berries (try to strain out seeds from the puree before adding it). I also use chocolate ganache, very strong coffee (to reduce the amount of liquid I need to add) and various extracts (raspberry, orange, lemon, coconut, almond, lavender…) Like with the balancing act, you may need to iterate in adding more until you achieve your desired flavor and intensity.
Final step: coloring. This Is done after flavoring because often the flavor will also add color (while food coloring rarely adds flavor). Whenever possible I prefer to stick with the natural coloring that came from whatever I used to flavor the frosting, but for special occasions I have been known to indulge in making it look more intense.
It turns out there is a trick to using food coloring well that requires an understanding of how it works. The pigment is actually contained within tiny bubbles, suspended in liquid. The motion of mixing the liquid will break some of the bubbles and release some pigment, but what really breaks them efficiently is heat. That’s why often when you eat something that’s been artificially colored, your tongue will end up deeply colored: the heat in your mouth releases a large amount of pigment that was still stuck inside the bubbles.
So here’s how we’re going to use this knowledge to our advantage. Scoop out 1/2 cup of frosting into a microwave-safe bowl. Add your desired color of food coloring to the bowl and mix it into the frosting. Microwave it on high for 5 seconds — this will slightly melt the frosting, but it will pop all the pigment bubbles. Take the frosting out of the microwave, and give it a quick stir (check out how intense the color suddenly became!) Now add, in increments, your colored frosting back into the main mixing bowl and mix on low to evenly spread the color throughout, repeating until you reach your desired color.
Beat the frosting on high for 30-60 seconds more at the end just to make sure it’s well mixed and to re-establish its firmness. You can now spread it into cupcakes, or pipe it from a bag — your choice.
There you have it: amazing cupcakes. Try it, have fun, and please post questions and/or comments here to let me know how yours turned out.