1 Preheat the oven to 200°C, gas mark 6.
2 To make the pastry, place the plain flour and salt in a large bowl and rub in the butter with your fingertips until it resembles breadcrumbs. Add the egg yolk and 3-4 tbsp orange juice to form a soft dough. Wrap in clingfilm and chill for 10-15 minutes.
3 Roll out the dough and line a 23cm wide, 4cm deep loose bottomed flan tin, leaving no more than 1-2cm excess pastry hanging over the edge. Place a large sheet of scrunched parchment paper inside the pastry case and fill with baking beans. Bake blind for 10 minutes, remove the beans and paper and continue to cook for 7-8 minutes. Cool slightly while you make the filling.
4 Whisk the stork, caster sugar and orange zest in a large bowl for 2-3 minutes until pale and fluffy. Whisk in the eggs 1 at a time and stir in the almond essence. Fold in the flour and cinnamon.
5 Spread the pastry base with jam and spoon over the cake mixture. Take 50g of the white marzipan and break into small pieces the size of a pea and scatter over the cake. Bake for 25 minutes or until golden and cooked through.
6 Divide the remaining marzipan into 11 and roll into balls, place on a baking tray lined with baking parchment. Place under a preheated grill for 1-2 minutes until golden. Place on top of the cake in a circle as soon as the cake comes out of the oven. Cool slightly before shaving off the excess pastry and removing from the tin. Best served while warm.