Mix the dried fruit, grated apple or pear, Demerara sugar, marzipan, cloves and cinnamon.
Divide the pastry into 6. Then assemble tarts one by one. Halve a chunk of pastry and roll out each halve to a circle about the thickness of a 50p piece on a floured surface. Spoon a sixth of the filling into the centre of one circle in a pile. Brush edges with egg, and lift the second pastry circle on top. Gently press down on the fruit to push out as much air as you can. Press the pastry edges to seal. Use an appropriate sized bowl, glass etc to help you trim the edges to a neat circle. At this stage, you can cover and chill the tarts overnight, or freeze for 1 month. Defrost before continuing. Brush with beaten egg, then make three small slashes with a knife in a row. Repeat with remaining pastry and filling.
Pop the tarts in the fridge while you heat oven to 200C/180C fan/gas 6. When the oven is nice and hot, brush tarts all over with egg and sprinkle each with a little more sugar. Bake for 20 - 25 mins, until golden, then eat warm with ice cream or custard.