Preheat your oven to 375 degrees. Line a baking sheet with parchment paper.
Combine the flour, sugar, baking soda, salt and orange zest in the bowl of an electric mixer. Mix using the paddle attachment on low speed. Keep the mixer running while adding the cubes of butter just a couple at a time. Continue mixing until the butter is incorporated. This can take about 3 to 4 minutes.
In a small bowl or a measuring cup, beat the egg then add the milk and orange juice and whisk to combine. Stream into the flour mixture while running on low speed. Add the cranberries and golden raisins and mix just until combined.
Dump the dough (it will be wet) onto a heavily floured board. Knead it very lightly into a round loaf. Place the loaf on the prepared baking sheet and lightly score an X into the top with a sharp knife.
Bake for 40 to 45 minutes or until a toothpick inserted in the center comes out clean. Cool on a baking rack. Serve warm or at room temperature.