1. First make the pastry. Beat the cream cheese vigorously with the butter, until well mixed and softened. Gradually beat in the flour.
2. Gather up into a ball, and wrap in foil or cling film. Chill in the refrigerator for 30 minutes.
3. To make the filling, mix together the muscovado sugar with the cinnamon, walnuts and raisins in a bowl.
4. Preheat the oven to 200ºC/gas 6.
5. On a lightly floured board, roll the chilled pastry out into a 30cm circle. Brush with beaten egg, and sprinkle the filling evenly over the pastry. Cover with a sheet of greaseproof paper, and run the rolling pin over it a couple of times to fix the filling firmly into the pastry. Lift off the paper.
6. Divide the circle up like a cake into 16 triangles.
7. Roll up each one, starting with the wider end, as if you were making a croissant.
8. Arrange on a baking sheet, brush with egg and sprinkle with caster sugar.
9. Bake in the oven for 12-15 minutes, until golden brown.