01 - Preheat oven to 400°F. Line a 12-cup muffin tin with paper liners or lightly grease with cooking spray.
02 - In a large mixing bowl, whisk together all-purpose flour, whole wheat flour, granulated sugar, baking soda, baking powder, salt, and caraway seeds if using.
03 - In a separate bowl, whisk together buttermilk, egg, and melted butter until smooth and well combined.
04 - Pour wet ingredients into dry ingredients and stir gently until just combined. Do not overmix; lumps in the batter are acceptable.
05 - Gently fold currants or raisins into the batter using a spatula until evenly distributed.
06 - Divide batter evenly among the 12 prepared muffin cups, filling each approximately three-quarters full.
07 - Bake for 16 to 18 minutes, or until a toothpick inserted into the center of a muffin comes out clean.
08 - Allow muffins to cool in the pan for 5 minutes, then transfer to a wire rack to cool completely.