On a floured work surface roll the pastry out to a 37cm/14½” diameter circle
Slice the marzipan into 1.5cm wide x 4mm thick strips.
Using a pastry brush and water, wet a 4cm/1½” border around the edge of the pastry. Lay the marzipan in a circle 5mm/¼” in from the edge. Fold the pastry and the marzipan over so creating a stuffed and raised edge for your tart. You don’t want the marzipan to escape during baking so use your finger to seal pastry edge onto pastry base. Place on a baking tray lined with baking paper.
Scatter the ground almonds over the tart base.
Cover the tart base with the apple slices and then scatter the caster sugar and hazelnuts over the apple. Bake in the preheated oven for about 25 minutes but check towards the end. The tart is ready when the crust is risen and golden.
Melt the apricot jam until it becomes liquid (I do this in a microwave) and paint over both crust and apple. Serve with cream, yoghurt, ice cream, crème fraîche or custard.
To prepare the marzipan I take a 100g/3½oz of shop bought marzipan, carve off 4mm slices, then cut each slice lengthways to give 1.5cm wide strips.