Preheat the oven to 450°F. Lightly dust a large baking sheet with flour and set it aside.

Sift the all-purpose flour, baking soda, and salt into a large bowl. Stir in the granulated sugar, golden raisins, and currants until evenly distributed.

In a separate bowl, beat the large egg and buttermilk together until combined.

Make a well in the center of the dry ingredients and pour in the egg–buttermilk mixture. Using a fork or one hand shaped like a loose claw, mix from the center outward just until the dry ingredients are moistened. Do not knead or overmix—the dough should be soft but not wet and sticky.

Turn the dough out onto a lightly floured surface. Gently bring it together as needed, then pat or press it into a long, flat rectangle about 1 inch high.

Cut the rectangle into mini scones. To make triangles, cut the rectangle into squares and then cut each square diagonally, or use a pizza cutter or knife to cut triangles directly.

Transfer the scones to the prepared baking sheet, spacing them so they do not touch and pulling each slightly away from the others.

Bake for 12 to 15 minutes, until the scones are golden on top and a skewer inserted into the center comes out clean.

Let the scones cool on the baking sheet a few minutes, then serve warm (with butter and jam if desired). Reheat as needed in the microwave.