Lightly grease a baking sheet. Dust a work surface with icing sugar, then roll out the pastry into a 35 cm (14 inch) round. Place on the baking sheet, arrange the marzipan slices in the middle and top with the halved apricots.
Scatter the almonds over the top, then fold the edges of the pastry up and over to form a rough border. Brush the pastry border with the milk and sprinkle with the caster sugar. Place in a preheated oven, 200°C (400°F), Gas Mark 6, for 25 minutes until the pastry is just cooked through. Serve with cream or custard.