Whisk the flour, baking powder, salt and nutmeg together in a large bowl.

Cut the cold butter into the flour until the mixture looks like coarse crumbs.

Stir in the sugar and currants.

Beat the egg with 2 tablespoons milk, then stir it into the flour mixture, adding the extra milk only if needed to bring the dough together.

Turn the dough out and pat it to about 1/4 inch thick on a floured surface.

Cut into rounds with a 2.5-inch cutter, gathering and re-patting scraps once.

Heat a griddle or heavy skillet over medium-low heat and melt a little butter across the surface.

Cook the cakes in batches for 3 to 4 minutes per side, until deep golden brown and cooked through in the center.

Check doneness by breaking one open: the inside should look dry and cakey, not doughy or pale.

Transfer to a wire rack and dust with granulated sugar while still warm.

Serve warm or at room temperature with a little extra butter alongside, within a few hours of cooking for the best texture.