Preheat oven to 180C/160C Fan/Gas 4 and line a baking tray with baking parchment
Mix the flour, sugar and baking powder in a bowl and rub in the butter until the mixture looks like breadcrumbs, then mix in the dried fruit.
In a bowl, beat the egg and milk together with the vanilla extract.
Add the egg mixture to the dry ingredients and stir with a spoon until the mixture forms a thick, lumpy dough. Add a little more milk if need to make the mixture stick together.
Place Spoonfuls of the mixture onto the prepared baking tray (choose how much depending on how big you want them). Leave space between them as they will flatten and spread out to double their size during baking.
Bake for 15–20 minutes, until golden-brown, depending on size. Allow to cool for a couple of minutes, then cool further on a wire rack. The rock buns keep well in an air tight container but are at their best on the day of baking.