Published March 1, 2009.
This easy wartime cake made with mayonnaise had a lot of good things going for it. Chocolate flavor wasn’t one of them.
With just a few ingredients (flour, sugar, cocoa powder, baking soda, vanilla, and mayonnaise, a stand-in for butter and eggs), we figured a dessert this easy had to have at least one hitch, and it did: The chocolate flavor was far from decadent.
We didn’t want to turn this snack cake into a pan of brownies, but could we ramp up the chocolate flavor enough to take the cake from good to great?
Increasing the cocoa powder was an obvious first step to boost chocolate flavor, but any more than a half cup turned the cake dry and chalky. We got the best results supplementing the cocoa powder with a little melted bittersweet chocolate. But we also had a trick to try: In other recipes using cocoa powder, we’ve intensified its flavor by “blooming” it in hot water first. Cocoa powder contains solid particles of fat and protein with tiny flavor molecules trapped inside. The hot water causes these flavor molecules to burst forth, amplifying flavor. But instead of blooming the cocoa in hot water, we used a hot cup of coffee to great effect—the chocolate flavor became richer with coffee as a silent partner. We also found that if the dark chocolate was chopped finely enough, it could be added to the cocoa to melt while the cocoa was blooming—no need to melt it separately in the microwave or double boiler.
Now it was time to think about the oddball ingredient in the mix: mayonnaise. We wondered if we could make the cake richer by replacing it with eggs and butter or eggs and oil. However, these cakes weren’t as moist and velvety as the mayonnaise version. Research revealed that oil, butter, and mayo each interact a little differently with flour. While all three coat the protein particles and reduce gluten development, creating a tender crumb, commercially prepared mayonnaise contains lecithin, an emulsifier that helps keep the oil suspended in micro-droplets. These small droplets greatly aid the oil’s ability to coat the flour’s protein particles, leading to a supremely tender cake. While butter and oil were out, the egg was a keeper. When compared to a cake made with mayo only to one with both the sandwich spread and an egg, the cake with egg had richer flavor and a springier texture.list of recipes