In a separate large mixing bowl, whisk together all of the dry ingredients until combined. Beat in the butter until it is fully incorporated into the flour. Don’t over mix it; it should be just combined and partially dry.
With a spoon or pastry brush, brush the tops of each cake/cupcake with an even layer of the simple syrup. You do not have to use a lot of the syrup; you just want to use enough to evenly coat the tops of the cakes.