On a floured surface, roll the puff pastry to 1cm/½in thick, then place half the butter over half the pastry. Fold the pastry over and roll to the original size.
Repeat with the remaining butter, fold over and roll once more. Cut out circles approximately 15cm/6in in diameter.
Preheat the oven to 220C/425F/Gas 7.
For the filling, melt the butter and sugar together, then add the currants, mixed peel and grated nutmeg. Mix well and leave to cool.
Spoon a spoonful of the filling mixture in the centre of each circle. Brush the edges with milk, then gather together over the filling and press together to seal.
Turn the cakes over, so the sealed ends are underneath, and using a rolling pin flatten to rounds approximately 1½cm/three-eighths in high.
Place on a baking sheet, slash the top three times, then brush with milk and sprinkle over the sugar.
Bake in the oven for 20-25 minutes until golden brown. They can be eaten hot or cold, but they are marvellous eaten with Lancashire cheese.
Trending This Week