01 - Preheat oven to 425°F. Line a baking sheet with parchment paper.
02 - In a large bowl, whisk together flour, baking soda, salt, and sugar until well blended.
03 - Stir in raisins or currants until evenly distributed throughout the flour mixture.
04 - Make a well in the center of the dry ingredients. Pour in buttermilk and melted butter. Mix gently with a wooden spoon or your hands until a shaggy dough forms; do not overmix.
05 - Turn dough onto a lightly floured surface. Gently knead just until it comes together, about 30 seconds.
06 - Shape into a round loaf about 7 inches across. Place on prepared baking sheet.
07 - With a sharp knife, cut a deep X across the top, about ½ inch deep, to help the bread expand as it bakes.
08 - Bake for 35 to 40 minutes, or until the loaf is golden and sounds hollow when tapped on the bottom.
09 - Cool on a wire rack for at least 20 minutes before slicing.