Preheat your oven to 375°F (190°C) and prepare a 12-cup muffin tin by greasing it.

In a large bowl, whisk together flour, baking powder, baking soda, and salt. Add sugar if desired.

Cut cold butter into the flour mixture until it resembles coarse crumbs.

Fold in the raisins or currants and caraway seeds if using.

In a separate cup, whisk together egg and buttermilk, then pour it into the dry ingredients.

Spoon batter into the muffin tin, filling nearly to the top. Brush tops with melted butter if desired.

Bake for 18 to 22 minutes until golden brown and a toothpick comes out clean.

Cool in the tin for 5 minutes before transferring to a wire rack. Serve warm.