From (with slight modifications) More Food That Really Schmecks, by Edna Staebler
This quick recipe can be even quicker if the butter is melted first, and the buttermilk is measured (and warmed ever so slightly). Preheat oven to 350 F.
1 1/2 cups flour
1 cup white sugar
3 rounded TB cocoa
1 tsp baking powder
1 tsp baking soda
1/2 tsp salt
Sift all the dry ingredients into a 9" x 9" cake pan. Stir them well to blend. Bump the pan up and down on the counter to level off. Prepare:
1 tsp vanilla
1 tsp vinegar
1/2 cup butter melted and cooled slightly
1 cup lukewarm buttermilk or sour milk
Make three hollows in the dry mixture with a spoon. Put 1 tsp vanilla in one hole; 1 tsp vinegar in another; and 1/2 cup melted butter in the third. Over all this, pour the lukewarm buttermilk. Stir and blend until it is smooth with no flour showing. Thump it on the counter again. Bake in a 350 oven for about 30 minutes. Leave it in the pan to cool.
Notes and Tips...
- Cocoa - her recipe did not specify the kind of cocoa - I have done it with both regular and Dutch-processed and have not noticed a big difference.
- Baking pan - I have always made this in a 10" round spring-form pan. Note that there is no "pan preparation" as in grease/flour or spray. I have no difficulty removing it from a spring-form pan - I suppose square pieces could easily be lifted from a square pan.
- Mix - sifting the ingredients into the baking pan helps to mix the ingredients; I use a mini-whisk if they need to be better blended; I use a fork when mixing in the wet ingredients - easier to ensure that all the flour from the edge is mixed in. As mentioned in the related blog post, this recipe is similar to the recipe for "Wacky Cake" and for that cake ATK advises "Using a wooden spoon or spatula, mix the batter, taking care not to over-mix; the batter should still contain a few streaks of flour." hmmm...
- Buttermilk - I suspect the reason she wants the milk to be lukewarm is to ensure it does not "solidify" the butter when they come into contact. I warm it in the microwave for about 10-15 seconds. When there is no buttermilk in the house, add 1 TB of vinegar or lemon juice to 1 cup of room temperature regular milk. The milk solids will curdle up a bit. This can be used right away.
- Baking Time - check this at 25 minutes - it may be ready.
- Best - this is best eaten the same day. Edna describes it as "moist, coarse and chocolate-y" - but it does tend to dry by the next day.
- Serving suggestions - can simply be sprinkled with icing sugar (or place a paper doily on top and then then sprinkle with icing sugar - resulting in a nice design; of course this has to be done once the cake is totally cool, otherwise the icing sugar begins to melt). The chocolate sauce in the photo? Chocolate-Brandy Sauce from Martha Stewart (can substitute other liqueurs for the Brandy...). This sauce keeps for weeks in the fridge - needs to be warmed a tiny bit before using.
- Icing - the easiest chocolate icing I ever came across - melt 6 oz / 175 g semisweet chocolate (chips) in a small heavy saucepan over low heat. Remove from heat and stir in 1/2 cup of sour cream. Beat by hand with a whisk until smooth. Chill a minute or so to spreading consistency. NB! Not ideal to do this too far ahead of serving time; this glossy icing stays soft and shiny only for an hour or so, and by next day, while still edible, it may be dull and a tiny bit leather-y. Of course, the cake may not last until the next day...