Grate the zest of the orange and lemon into the bowl then cut each fruit in half, squeeze out the juice, and add to the bowl.
Mix thoroughly and set aside for the fruit to plump up in the juice. Ideally, do this the day before.
Place the soft butter and sugar into a large mixing bowl and cream together until the mixture is light and fluffy. You can use an electric hand whisk to do this.
Crack the eggs into a bowl and beat them together lightly with a fork.
Gradually beat the eggs a little at a time into the butter and sugar mixture. Don’t worry if the mixture seems a little curdled.
Sift the flour, baking powder, mixed spice and salt over the bowl and fold in carefully using a metal spoon.
Stir in the ground almonds, followed by the fruit and juice mix.
Carefully spoon half the mixture into the base of the prepared cake tin.
Cut off one third from the block of marzipan and on a work surface dusted with a little icing sugar roll it into a disc to fit neatly into the cake tin.
Lay the disc of marzipan over the cake mixture and press down lightly, then spoon the remaining cake mixture neatly over the top.
Bake in the centre of the oven for approximately 1 hour until the cake is golden and springy and a metal skewer inserted into the centre comes out clean.
Leave the cake to cool in the tin then unwrap and remove the lining paper.
Sieve the apricot jam into a small saucepan and warm over a gentle heat.
Taking another third of the marzipan, roll out to form a disc that will fit neatly on top of the cake.
Brush the top of the cake liberally with the apricot jam then lay the marzipan on top, trimming the edges if necessary. You may choose to crimp the edges to give a decorative effect.
Use the remaining marzipan to make eleven or twelve even sized balls to represent the twelve Apostles – depending on whether or not you choose to include Judas!
Use a little of the egg white to attach the balls evenly around the top of the cake.
Lightly brush the top of the cake and the balls with the remaining egg white and place under a heated grill for a few minutes until the marzipan is lightly browned in places. This will only take a few minutes so watch the cake to make sure it doesn’t catch!
Store in an airtight tin ready to serve over Easter.