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 until evenly distributed.
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 just until combined; the dough should remain slightly shaggy. Do not overmix.
06 - Turn the dough onto a lightly floured surface. Gently pat into a disk about 1 inch thick. Cut into 8 equal wedges.
07 - Transfer wedges to the prepared baking sheet, leaving space between each. Brush tops with buttermilk and sprinkle with coarse sugar if desired.
08 - Bake for 16 to 18 minutes until golden brown and a toothpick inserted into the center comes out clean.
09 - Cool on a wire rack for 5 minutes. Serve warm or at room temperature.