01 - Preheat oven to 400°F. Line a baking sheet with parchment paper.
02 - In a large bowl, whisk together all-purpose flour, whole wheat flour, sugar, baking soda, baking powder, and salt until well blended.
03 - Add cold, cubed butter to the flour mixture. Using a pastry cutter or your fingertips, work the butter into the flour until the mixture resembles coarse crumbs with some pea-sized pieces remaining.
04 - Stir in raisins or currants and caraway seeds if using until evenly distributed throughout the flour mixture.
05 - In a separate bowl, whisk together buttermilk and egg until fully incorporated.
06 - Pour the buttermilk mixture into the dry ingredients. Stir with a spatula or wooden spoon just until combined and dough begins to form. Do not overmix.
07 - Turn dough onto a lightly floured surface. Gently pat into a 1-inch thick circle. Cut into 8 wedges or use a round cutter for traditional round scones.
08 - Transfer scones to the prepared baking sheet, leaving space between each. Brush tops with buttermilk and sprinkle with coarse sugar if desired.
09 - Bake for 16 to 18 minutes until golden brown on top and a toothpick inserted in the center comes out clean.
10 - Let scones cool slightly on the baking sheet, then transfer to a wire rack. Serve warm or at room temperature.