Friday, January 27, 2012

Happy Chocolate Cake Day!

Early this morning I learned today is Chocolate Cake Day. Therefore, I felt duty-bound to bake a chocolate cake and write about it so that you, gentle reader, may have some inspiration and tips for baking your own tasty treat. So this is all for you. Don't say I never did anything for you!

Before I get into the how-to's and why-for's of this cake--as well as the results of a little experiment I ran on cocoa--let me talk a little about cake. Cake is one item I have had a lot of trouble with since transitioning to a mostly local and/or organic and scratch-made diet. In my family, we always bake a cake for one another's birthdays. In years past, that has meant going to the grocery store, getting a box of cake mix and a tub--oh all right, two tubs--of chocolate frosting and making a moist cake with creamy deliciousness smeared all over it. But, with our commitment to avoiding most industrial food, this is no longer an option and so we have to bake our cakes from scratch.

And it turns out a lot of science, technique, and finesse goes into baking a good cake; thus, much trial and error ensued. I've made a few disasters: flat, dense, dry bricks with hard frosting crusting the top. Not good. (Not that my little boy minded: sweet is sweet as far as he's concerned.) I tried changing the flour I used to cake flour, still not getting the result I wanted. (And it was a big mistake, I think cake flours are really only for very light and airy cakes, like angel food cake.)

Then, for my last birthday, my husband had a breakthrough and made a wonderful moist cake. What was the difference? Using vegetable oil instead butter. Naturally my husband, the scientist, made this discovery after doing his research. First: Define the problem. What did I want out of a cake? Light and airy, or soft and moist, but not so dense you could, say, pound in a nail with it? I wanted something moist and rich with a springy crumb. Something that would feel chocolate-y and unctuous on the tongue. And I didn't want it to get dry and crumbly when you put it in the refrigerator for a day.

Once he knew what I wanted, he hit the books, or, to be more precise, a book, Shirley O. Corriher's BakeWiseto uncover the secrets of a moist cake. And voila, he hit pay dirt. Here's what Corriher says about using oil in cakes, "Oil coats flour proteins better than a solid fat and prevents their absorbing liquid from the batter to make gluten. This leaves more moisture in the batter. Cakes made with oil can be not only tender but also very moist."

Aha! So because we were using butter in our cake, we were losing moisture. Furthermore, we were developing gluten, which naturally toughens up a dough (a great feature in bread, not a great quality in cake). Obviously, the taste of butter is incomparable, so we were hesitant to use oil, but then decided to give it a try, realizing that most box cakes we had ever made included oil. Mike tried an oil-based recipe that he found in Tish Boyle's The Cake Book with great results. I've used the same recipe below, with the difference that I replaced the recipe's whole milk with buttermilk. (Why? Well, I have a lot of it, for one thing. Also, the acidity in buttermilk reacts with the baking soda, so I wanted to see what, if any, effect that would have on the final cake. However, because baking powder, which contains its own acid, is also in the recipe, it may not make much of a difference at all. Mostly, my chimp curiosity was to blame.)  

Before I get into the cake recipe, here's another thing I was curious about: the red in red velvet cake. Traditionally, the red in red velvet cake came from a reaction in the cocoa when you added an acid (vinegar or buttermilk), which would bring out the reds in the cocoa. Because I had the cocoa out anyway, I decided to test this. It didn't really work. I was sad. I was hoping for a dramatic transformation. I don't know why nothing happened; it may be the cocoa made now has somewhat different chemical properties than it used to have. Here are some before-and-after pictures (actually I think there's more red in the before picture, but that may have been caused by the light):

Before: A slurry of cocoa powder and water
After: Here I added a couple tablespoons white vinegar. No change. Sigh. 
Now, on to the recipe for the cake.

Devilishly Moist Chocolate Cake
[Adapted from Tish Boyle's The Cake Book]


  • 1 and 1/3 cups all purpose flour
  • 3/4 cup cocoa (not Dutch process)
  • 1 and 1/4 teaspoons baking powder
  • 1/2 teaspoon baking soda
  • 1/4 teaspoon salt
  • 1 and 2/3 cups granulated sugar
  • 1/3 cup neutral-flavored vegetable oil (such as canola, safflower, etc.)
  • 2 large eggs
  • 1/3 buttermilk (or whole milk)
  • 2 teaspoons vanilla extract
  • 1 cup boiling water

Turn on the oven to 325 degrees (Fahrenheit). Butter and flour a nine-inch pan (spring form is nice; it's so much easier to get the cake out).

Mix dry ingredients (flour, cocoa powder, baking powder, baking soda, and salt) into a stand-mixer bowl. Using a paddle attachment on slow speed, gently mix these ingredients until they are evenly distributed. Then add the sugar and do the same thing.

Next, while the mixer is going at slow speed, pour in the oil. Mix for a few minutes until the oil is evenly distributed and the mix sort of looks like crumbly sand.

Now, in another small bowl, whisk the eggs until blended. Add vanilla extract and buttermilk to the eggs and whisk until blended. (Make sure at this point that you've got water boiling. I almost forgot.) With the mixer on low speed, add the egg mixture, stopping the mixer to scrape down the sides of the bowl from time to time. (And don't be afraid to make a mess of your kitchen.)

Now, add a little bit of boiling water at a time, letting the mix get smooth until you add the next bit. Make sure to scrape down the sides. Mix until smooth, but no more. Pour the batter into the pan you've prepared and slide it into the oven. Bake for 45 minutes, then test for doneness by sticking a toothpick into a few center spots in the cake. If they come out clean, take the cake out of the oven. If there are wet crumbs on the toothpick, leave it for as much as 10 more minutes.

Let the cake cool a few minutes in the pan before removing it. Let it cool completely before frosting it.

Dark Chocolate Sour Cream Frosting
[from Tish Boyle's The Cake Book]


  • 6 oz bittersweet chocolate, chopped or broken into pieces
  • 1/2 cup unsalted butter, softened
  • 1/2 cup sour cream, room temperature
  • 2 and 1/2 cup sifted powdered sugar
  • 1 teaspoon vanilla extract

Melt the chocolate by placing it in a heat-safe glass (like a Pyrex measuring cup) in boiling water (make sure that water doesn't boil into the chocolate; it will change the chocolate's texture in undesirable ways). Set it aside to cool until it's comfortable to touch. (This is important, otherwise you'll cook the sour cream and melt the butter, which would result in a kind of icky mess.)

Put the butter into your mixer bowl and beat it with the paddle attachment until it's creamy. Add the sour cream and beat until smooth.

Add a little confectioner's sugar at a time and beat until the mixture is light and creamy. (When you add the sugar, start the mixer on slow and bring up to higher speed. Otherwise you will have an exciting powdered sugar explosion in your kitchen.) Beat in the vanilla extract.

Finally, add the cooled chocolate, a little at a time. Scrape down the sides of the bowl a few times. When you have brought together all the ingredients, beat the frosting for a minute or two so it gets fluffy. Then spread it on your cake. (I am not much of a cake decorator, so I am afraid I can't give you any tips, other than spread a thin layer first to "glue" down the crumbs--also called a crumb layer.)

If you want to make it a layer cake, I have added some pictures below for a handy way to halve your cake evenly (learned this trick from Williams & Sonoma Tools & Techniques). Me? I am going to eat some cake. And then I've got to clean up this mess!


  1. This is one of my favorite: Chocolate Cake. Never fails and never will change.

  2. The reaction between the acidic ingredients and the cocoa happens during the baking process and is apparent after it is baked. Have you ever noticed reddish hues in chocolate cake? that's what they're talking about, however it's not very red and that's why people add copious amounts of food coloring to red velvet. So you didn't do anything wrong in your experiment :-)

    BTW, this is a great chocolate cake.