Adapted from Melissa Clark, this spin on Marian Burros's classic plum cake features nutty spelt flour, a hint of Cognac, and fragrant vanilla beans.
Combine flours, baking powder, and sea salt in a small bowl. With mixer on low, add half the flour, then the milk, and finally, add the remaining flour.
Cool completely on a wire rack before serving with a dollop of whipped cream or crème fraîche.