Chocolate Mayonnaise Cake

This super simple chocolate cake is gluten-free and fructose-free, but it has a delicate crumb and a mellow chocolate flavor. Frost it with Chocolate Kahlua Buttercream for a winning combination. It keeps well in the refrigerator if there are left-overs, so nothing goes to waste. In fact, if you heat a refrigerated slice in the microwave for 5 to 10 seconds, it will taste like it just came out of the oven and the buttercream will form a luscious sauce. This is one of those recipes that was wildly popular thirty or forty years ago because it’s easy to make and it tastes great, which is true for this updated version as well.

Prep tip. Mix up a batch of gluten-free flour and substitute 200 grams (7 ounces) of it for the brown rice flour, potato starch and tapioca starch in the cake recipe. The proportions for the flour blend follow the recipe.

June 7, 2013:  Cocoa powder recently tested moderately high in FODMAPs at the Monash University lab, which means this recipe may no longer be considered suitable for a low-FODMAP diet. Here’s a link to what dietician Patsy Catsos has to say on the topic:

Chocolate Mayonnaise Cake

Serves 10, adapted from “The Cake Bible”

30 grams (1/3 cup) unsweetened cocoa (nonalkalized, such as Hershey’s)
295 grams (1 1/4 cup) boiling water
2 tablespoons (30 ml) ground flax-seed
1 teaspoon (10 ml) vanilla
160 grams (3/4 cup) mayonnaise (not reduced calorie)
134 grams (3/4 cup + 2 tablespoons) super fine brown rice flour
44 grams (1/4 cup) potato starch
22 grams (3 tablespoons) tapioca starch
200 grams (1 1/2 cups) dextrose
2 teaspoons (10 ml) baking soda
1/2 teaspoon (2.5 ml) salt

Heat the oven to 350 degrees F. Grease two 8 by 1 1/2 inch cake pans and line the bottoms with parchment or wax paper. Grease the paper lining, then use sweet rice flour to dust the bottoms and sides so that no bare spots show. Tap the pans sharply against a hard surface to remove any excess flour and set the pans aside. In a medium size bowl, whisk together the cocoa, flax-seed  and boiling water until smooth. Let cool to room temperature, then whisk in the vanilla and the mayonnaise.

Put  the remaining ingredients into a large mixing bowl and mix them together on low-speed for 30 seconds. Add the chocolate mixture and mix on low until combined. Mix on high-speed for a minute, scraping down the sides of the bowl a couple of times. Pour half of the batter into the prepared pans and put them on the center rack of the oven. Bake for 20 to 25 minutes, or until the center of the cake springs back when lightly touched and a toothpick inserted in the middle comes out clean. Let the cakes cool in the pans for 10 minutes after removing them from the oven. Loosen the sides with a knife and carefully turn the layers onto a wire rack to finish cooling. Don’t frost the layers until they are completely cool.

Gluten-free Flour Blend

600 grams (21 ounces) superfine brown rice flour
200 grams (7 ounces) potato starch
100 grams (3.5 ounces) tapioca flour

Mix the ingredients together in a stand mixer or whisk them together in a large bowl. Transfer the flour blend into a large glass jar or a plastic zip lock bag and store it in the fridge or freezer.