6ounces(1 1/2 sticks) unsalted butter, cold and cut into small pieces
1tablespoongrated orange zest
1ounce(1/4 stick) unsalted butter, melted, for brushing
Preheat the oven to 425 degrees F.
In a medium bowl, whisk together the flour, sugar, baking powder, baking soda, and salt.
Add the cold butter pieces and, using your fingers, a pastry blender or a bench scraper, work the butter into the dry ingredients until the mixture resembles coarse cornmeal. It's fine to leave a few larger pearls of butter in the mix; they'll add to the scones' flakiness.
Add the buttermilk and zest to the bowl and use a fork to mix the ingredients until they are just combined. The dough will look soft and rough.
Gather the dough into a ball and place it on a lightly floured surface. Kneed it for a dozen turns. Cut the dough in half.
Roll out one piece of the dough into a circle that's around 1/2 an inch thick and 7 inches wide. Brush generously with butter and sprinkle a tablespoon of sugar on top. Cut the circle into 6 triangles and place on a baking sheet lined with parchment. Repeat with the second half of the dough.
Bake for 10-12 minutes, until both the tops and bottoms are golden. Serve warm or at room temperature.