This will yield one 3-inch three-layer mini cake, or about four cupcakes.
I’ve also made this recipe using 1/4 tsp baking powder and 1/3 cup flour — the extra leavener plus a little less flour will yield a more delicate crumb. The recipe above is still moist, but sturdier and a bit denser. With such small-scale recipes, the weight of the flour can make a big difference, so try for a lighter hand when scooping or use a kitchen scale if you have one.
The frosting recipe above may not be enough for a really thickly iced cake, so you may want to double it — either for insurance, or, you know, just to eat with a spoon.