1 lb (480 g) plain white flour
1 level teaspoon baking soda
1 level teaspoon cream of tartar
2 oz (60 g) butter
4 oz (120 g) sugar
4 oz (120 g) raisins
1 egg, beaten
1/2 pint (300 mL) buttermilk
Preheat oven to 200°C (400° F). In a bowl, sift the flour with the baking soda, cream of tartar, and salt, and rub in the butter until it resembles breadcrumbs. Add sugar and raisins and mix through. Add the egg and buttermilk, mixing well with a knife. Knead lightly and shape the dough into a round of about 3 in. thickness. Mark the top with a cross using a knife. Bake on a greased baking tray for 45 minutes or until golden brown—the base should sound hollow when tapped.
A Trifle, A Coddle, A Fry: An Irish Literary Cookbook by Veronica O’Mara and Fionnuala O’Reilly.
It's easy enough to leave out raisins if desired!