Preheat the oven to 220°C.
Break the chocolate into pieces and melt in a bowl over a saucepan of boiling water. Add the sugar stir until mixture is well blended and fluffy. Add almonds, chocolate, two eggs and cinnamon.
Unroll the a roll of the pastry on a flan tin and prick a few holes in the base. Spread the centre with the chocolate mixture and spread up to 2cm from the edge. Add the sour cherries by placing them in the mixture. Cover with the second pastry sheet and using your fingers, flour and water pinch the two pastry layers together and mark the edges with a fork.
With a brush, glaze the surface of the cake with egg yolk, then use a knife blade to make a design. Finally, prick the dough in several places to prevent it from swelling. Bake the cake for 30 minutes until its golden brown, if not cooked sufficiently, cook for a further 5-10 minutes in oven.
Freezing and defrosting guidelines
Bake according to the recipe but stop before adding decoration or icing if called for. Allow to cool completely. Wrap well in clingfilm and tin foil (to prevent freezer burn) and freeze for up to 3 months.
Loosen the tin foil and clingfilm but leave to defrost in packaging at room temperature for several hours before serving. If you wish to serve the baked goods warm, place them on a baking sheet for 10 minutes in a moderate oven.
If you wish to add icing or decoration, add them after the baked goods have fully defrosted and are at room temperature.