Preheat your oven to 375°.
In a large bowl whisk together the flour, baking soda, salt and sugar.
Cut the butter into ½” cubes and add to the flour mixture. Using your hands, toss to coat the butter with flour. Start to squeeze the butter into the flour with your fingers and continue until the mixture looks like very coarse cornmeal.
Add the currants and toss to combine.
In a 1 cup measuring cup measure out the buttermilk, add the egg yolk and whisk to combine.
Make a well in the center of the flour/butter mixture and pour in the buttermilk/egg yolk mixture.
Using a spatula, gently stir the mixture until it starts to come together, it will be sticky. If the mixture looks dry add a tablespoon or two of buttermilk.
Lightly flour your work surface and dump out the dough. Gently bring the dough together and form it into a ball.
Place the dough onto a parchment lined baking sheet
Sprinkle the top with about 2 teaspoons of granulated sugar.
Slice a cross into the top about ½” deep.
Bake for 30-35 minutes or until golden brown, the bottom sounds hollow when tapped and the internal temperature is about 195℉ when taken with an instant read thermometer.
Allow the bread to cool completely before slicing and enjoying.

Tina’s Classic Irish Soda Bread