Gather all ingredients. Preheat the oven to 375 degrees F (190 degrees C). Line a baking sheet with parchment paper or a silicone baking mat.

Whisk all-purpose flour, whole wheat flour, oats, salt, baking soda, and baking powder together in a large bowl. Cut butter into flour mixture using a pastry blender until mixture resembles coarse crumbs.

Beat buttermilk, egg, honey, and orange zest together in a medium bowl. Pour buttermilk mixture, currants, and raisins into flour-butter mixture; stir with a wooden spoon until a wet, sticky dough comes together.

Turn dough out onto a well-floured work surface; press dough together into a ball and cut into 2 equal pieces. Form each into a smooth, round loaf.

Transfer to the prepared baking sheet and let rest for 15 minutes. Cut a 1/2-inch-deep “X” into the top of each loaf using a serrated knife.

Bake in the preheated oven until golden brown and fragrant, about 45 minutes. Transfer loaves to a wire rack to cool completely before slicing.

Enjoy!