01 - Preheat the oven to 400°F. Line a baking sheet with parchment paper.
02 - In a large bowl, whisk together the all-purpose flour, whole wheat flour, sugar, baking soda, baking powder, and salt until well blended.
03 - Stir in the raisins or currants and caraway seeds if using.
04 - In a separate bowl, whisk together the buttermilk, egg, and melted butter until smooth.
05 - Pour the wet ingredients into the dry ingredients. Mix gently with a fork until just combined; do not overmix as this will toughen the dough.
06 - Turn the dough out onto a lightly floured surface and pat into a circle about 1 inch thick.
07 - Cut into 8 wedges and transfer to the prepared baking sheet, spacing them apart for even baking.
08 - Brush the tops with buttermilk and sprinkle with coarse sugar if desired.
09 - Bake for 16–18 minutes, or until golden and a toothpick inserted into the center comes out clean.
10 - Cool on a wire rack. Serve warm or at room temperature.