1) Heat your oven to 200 degrees C.
2) To make the pastry place the cold butter into a food processor with the sieved flour and lemon zest. Blitz until the mixture becomes the texture of breadcrumbs.
3) Whisk the sugar into the egg then pour into the machine with a splash of water. Blitz just long enough for the mixture to form a ball. Remove with your hands and ensure you have a nice firm ball by moulding with your hands. Wrap in cling film and leave in
Meanwhile halve and stone your apricots then place on a baking tray cut side up. Sprinkle all over with the demerara sugar then roast in the oven for 15-20 minutes until they are soft to the point of a knife but not falling apart.
4) Once rested prick all over the base with a fork then line with parchment paper and follow with baking beans. Bake blind for 15-20 minutes until the base is just beginning to crisp but has not browned. Remove the beans and allow to cool.
5) Spread your crumbled amaretti all over the base then top with a layer of apricots.
6) In a large bowl whisk the eggs and sugar together until light and fluffy. Remove the vanilla seeds from the pod and whisk into the egg mixture along with the Jersey cream.
7) Place the tart onto a baking tray then carefully pour over the custard mixture.
8) Allow to cool before slicing and serving with creme fraiche, plenty of icing sugar and an edible flower.
9) For the syrup: warm the jam. Add the amaretto. Heat until bubbling and allow to cool just above room temperature and pour over the cake.