The Amazing 1-Minute Chocolate Cake


Heather Horn

To try Heather's recipe for microwave chocolate cake, click here.

"RE: The 5-minute chocolate cake e-mail. How desperate are you?" asked the headline of a King Arthur Flour blog post. Though not a particularly polite question to ask a confirmed dessert addict, it's certainly a fair one. The King Arthur Flour blog may well be the best blog for home bakers on the Internet, and people who like messing around with flour tend to take a certain pleasure and pride in traditional recipes, and even recipe complexity. It's what separates us from midnight food-crammers—we consume carbs, we tell ourselves, for the process, not the piggery.

So readers of the Bakers' Banter blog, as it's called, aren't likely to take too kindly to microwave baking. Still, there are things in life worth sacrificing one's pride for, and chocolate cake, I'm convinced, is one of them. That's how I wound up being drawn into the rabbit hole of microwave cakedom. The King Arthur Flour heroes had taken it upon themselves to improve a substandard recipe from a chain e-mail, transforming a nearly inedible 5-minutes-in-a-mug microwave cake into something more palatable.

I kept it simple with five ingredients—semisweet chocolate, butter to improve the texture and keep the chocolate from seizing up, sourdough starter, the obligatory baking soda to balance the sour starter, and a pinch of salt.

I decided to give it a go. Theirs was an eggless version involving cocoa powder, flour, sugar, baking powder, etc.—all the usual suspects. Alas, as the bloggers themselves admitted, it wasn't that great; the vaguely molten texture was about right, but it tasted like DC tap water—certainly not worth the effort of the 11 ingredient measurements required. So I sighed, told myself the idea of microwave chocolate cake was a bit gross and slothful to begin with—and nevertheless promptly returned to the recipe when I got a nighttime dessert craving. A project formed: to make a real chocolate cake in the microwave, if it could be done.

It turns out that it can be done. What's more, it can be done well, with few ingredients, and—even better—a healthy dose of food snobbery to make up for the shame of the microwave.

I began to mess around with the King Arthur recipe, adding butter to get rid of that watery taste, subtracting flour to make the whole thing denser and more chocolatey. Eggs, I quickly found, were a waste of time. One egg for a single mug or bowl's worth of baking is a lot of egg, and eggs do strange things in the microwave. Adding fat, on the other hand, was definitely the right idea.

But I never quite got the texture right, and in terms of taste, I never quite lost the sense that I had started with a packet of chocolate pudding mix and a pound of sawdust, adding different proportions of water and cholesterol at will.

This, I decided finally, was the fault of the cocoa powder—cocoa powder and I have a tense relationship. The experiment languished until I found myself at the kitchen counter one night with a bag of Nestle chocolate chips at my elbow.

Baking experimentation is not, as some would have you believe, impossible, but it does usually require a starting conceit—a model, if you will. Mine, I figured, contemplating the chocolate chips, would be a French-style chocolate cake—the kind my simplicity-loving father taught me when I was little, which relies on chocolate and butter melted together, egg yolks, and tiny amounts of flour and sugar, with egg whites folded in for structure at the last minute.

The differences here, I thought, would largely be of scale. Also, I would not separate the eggs and whip the egg whites here—far too much work for a recipe designed to be simple. I did, however, beat the egg thoroughly in the hopes of stuffing some air into the concoction to hold it up.

Failure again: I did not, unfortunately, get five-minute chocolate cake. Instead, I got something akin to a greasy soufflé, puffing up magnificently in the microwave and then sinking back down into something strongly resembling—in both appearance and taste—a wet, shiny chocolate dish sponge.

So I upped the flour and added baking powder, in the hopes of at least preventing the soufflé from collapsing as quickly. That actually worked, and with the solid chocolate instead of the cocoa it didn't taste half bad—somewhere between a regular chocolate cake and a chocolate angel food cake. But it wasn't a cake I would risk my baking dignity for—between the extra flour and nuking the bejeezus out of the mixture for fear of salmonella, all the fudgy moltenness I'd been hoping for wasn't an option. Again I considered myself stumped.

I didn't exactly give up. Busyness got in the way, as did a great desire not to become an obesity statistic. I'd also neglected nearly everything else in the kitchen. My beloved sourdough starter, for instance, was starting to look and smell a bit the worse for wear.

Thus the Great Chocolate Project was put on hold as I turned my attention to finding enough sourdough recipes to keep me using—and thus feeding—my starter until it was nursed back to health. In the middle of a pancake batch, inspiration struck.

Sourdough pancakes are a remarkable breed—the sourdough provides both moistness and structure, and you wind up being able to omit eggs if you so choose. The thought that occurred to me, then, as I recalledthe chocolate cake, was this: what if you could sub in sourdough for both the eggs and the dry leaveners (baking powder, mostly), avoiding the egg-in-the-microwave problem?

It was unorthodox. It also turned out to be perfect.

I kept it simple with five ingredients—semisweet chocolate, butter to improve the texture and keep the chocolate from seizing up, sourdough starter, the obligatory baking soda to balance the sour starter, and a pinch of salt—and success came immediately (though, as it turns out, the recipe is a little better if you add vanilla). The resulting cake is dense, moist, and chocolatey, resembling nothing so much as a perfect marriage of fudgey brownie and—where the sourdough isn't quite cooked or the chocolate didn't quite mix in—molten chocolate cake. Nor is there any need to worry about salmonella in the uncooked bits, unlike with egg versions. The starter acts almost like those egg whites I'd skipped—adding structure before baking.

The best part by far, though, is the mitigation of baker's shame: the sourdough goes a long way toward making up for the indignity of baking in a microwave. There's something irretrievably "foodie" about sourdough starter; I can have my cake and my baking snobbery, too.