Chocolate Depression Cake

Preparation - Preheat the oven to 350°F. Grease an 8-inch square pan.

Bloom the cocoa - Bloom the cocoa: In a medium bowl, add the cocoa powder and whisk in the hot coffee or boiling water until the cocoa powder has dissolved completely.

Make the batter - Make the batter: Add the granulated sugar, brown sugar, oil, vinegar, and vanilla extract to the cocoa mixture and whisk until combined. The oil likely won't fully incorporate and will float on top. That's OK. In another large mixing bowl, whisk together the flour, baking soda, and salt. Pour the wet ingredients into the dry ingredients and fold with a rubber spatula until fully combined and there are no pockets of dry flour.

Bake - Bake: Pour the batter into the prepared pan. Bake for 25 to 30 minutes, or until the cake has domed and a toothpick inserted into the center of the cake comes out clean. Let the cake cool to room temperature in the pan set on a wire rack, 45 minutes to an hour.

Make the glaze - Make the glaze: When the cake has cooled, prepare the chocolate glaze. In a medium bowl, whisk the powdered sugar, cocoa powder, and salt. Pour in the vanilla extract and 1 tablespoon of cooled coffee or water. Combine with a whisk, adding more coffee or water 1 teaspoon at a time until it reaches your desired thickness. It should be thick but pourable, similar to chocolate ganache or hot fudge sauce.

Glaze the cake - Glaze the cake: Pour the chocolate glaze over the cooled cake and spread it in an even layer with an offset spatula or a butter knife. Serve immediately, or let the glaze set. Store the cake, covered tightly, at room temperature for up to 4 days. For longer storage, freeze the cake for up to 3 months. To freeze, wrap the cooled, unglazed cake in one layer of plastic wrap and one layer of aluminum foil. Thaw the cake, still wrapped, in the fridge overnight.