Directions

1. Preheat oven to 350 degrees. Line a baking sheet with parchment paper; set aside. Whisk together the flours, salt, baking soda, and baking powder in a large bowl. With a pastry blender or your fingertips, blend in butter until it resembles small peas. Add buttermilk all at once; stir with a fork until mixture holds together.
2. In the bowl, pat the dough into a domeshaped loaf about 7 inches in diameter. Lift out dough; transfer to lined sheet.
3. Lightly dust top of loaf with flour. Cut a 3/4-inch-deep cross in top, reaching almost all the way to edges. Bake, rotating sheet halfway through, until deep golden brown and a cake tester inserted into the center comes out clean, about 1 hour and 20 minutes. Let cool on a wire rack.