I almost always have a box of Ghirardelli Dark Chocolate brownie mix in my pantry. At this moment I have about five pounds of the the stuff. (You can buy seven pounds at a time at a restaurant supply store, which is the amount A.A. Newton gave me for my birthday.)
I really adore brownies, but—even with how easy boxed mix brownies are to execute—I don’t always want to make an entire batch, mostly because I will consume that entire batch in approximately 36 hours. Luckily, one can use brownie mix to make a very chocolatey cake for one. You just need a little sour cream.
I started out making this “cake” with 1/4 cup brownie mix and 2 tablespoons water, and it was okay, but then our managing editor Joel Cunningham mentioned his wife makes a very similar treat using yogurt instead of water. I didn’t have any yogurt, but I had sour cream (because I simply must have it in the house at all times), so I gave that combination a whirl.
It worked beautifully. The sour cream gives the cake a little more substance and lovely little bit of lactic tang. If you get a mix with chocolate chips, you get an almost lava cake-like effect.
You can cook the cake in the microwave or in an air fryer (or other small convection oven), but the air fryer will bake a better cake. Microwave cakes (like the one directly above this paragraph) come out slightly damp and rubbery (but not bad); cakes cooked in the air fryer (like the one at the top of this blog) come moist but fluffy with a thin, shiny crust on top.
No matter how you cook it, the ratios are the same. Simply combine 1/4 cup brownie mix and 2 tablespoons of sour cream in a greased mug or ramekin and stir with a fork until you have a smooth batter, then cook the cake in the microwave for one minute, or an air fryer for 10 minutes at 350℉. Let cool for a minute or two before enjoying. Repeat as needed.