Preheat oven to 400°F (200°C)

Place the butter in a small saucepan over low heat until just melted, then remove from heat and add the rest of the filling ingredients, stir to combine and set aside to cool.

Roll out the dough to a rectangle measuring about 6″ x 15″ (16cm x 40cm), cut lengthwise in half, then cut into 10 equal sized pieces.

Place a spoonful of filling onto the center of each square, using all of it evenly between the 10 pieces, then wet the edges of one of the squares, using your finger.

Now, hold the pastry in one hand and close the edges together to seal the filling inside, forming it into a round shape when finished.

Place the pastry on a lined baking sheet, with the pinched side down and press down slightly.

Repeat with the remaining 9 pastries, then make three slits on top with a very sharp knife or razor blade, brush with the beaten egg white and sprinkle with sugar.

Pop into the preheated oven, on a lower shelf for 10 minutes. After 10 minutes, place the tray in the middle of the oven for a further 5 to 7 minutes or until golden brown. Remove from tray and place on cooling rack.