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 butter into flour until mixture resembles coarse crumbs with some pea-sized pieces remaining.
04 - Stir in raisins or currants and caraway seeds if using, distributing evenly throughout the flour mixture.
05 - In a separate bowl, whisk together buttermilk and egg until combined. Pour into dry mixture and stir with a wooden spoon just until dough comes together; do not overmix.
06 - Turn dough onto a lightly floured surface. Gently pat into a 1-inch thick circle, handling minimally to maintain tenderness.
07 - Cut circle into 8 equal wedges or use a round cutter for traditional round scones.
08 - Transfer scones to prepared baking sheet, spacing 2 inches apart. 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 into the center comes out clean.
10 - Let scones cool on baking sheet for 5 minutes, then transfer to a wire rack. Serve warm or at room temperature.