Line a deep 20 cm cake tin. Heat oven to 160°C fan (180°C conventional).
Cream butter and sugar until pale and fluffy. Beat in eggs one at a time. Fold in flour, baking powder and spice, then stir in dried fruit, cherries, lemon zest and milk to give a soft dropping mixture.
Roll one third of the marzipan into a circle to fit the tin. Spoon half the cake mixture into the tin, level, place the marzipan layer on top, then cover with remaining mixture and smooth.
Bake for about 1 hour 45 minutes to 2 hours. If the cake browns too quickly, cover loosely with foil. It is ready when a skewer comes out clean. Cool fully in the tin.
Warm the apricot jam and brush over the top. Roll another marzipan circle and place on the cake. Shape the remaining marzipan into eleven equal balls and arrange around the edge.
Brush lightly with beaten egg and place briefly under a hot grill, or use a blowtorch, until lightly golden. Watch carefully as marzipan colours very quickly.
Notes
The middle marzipan layer is essential for a true Simnel cake. Bake low and slow to keep the fruit moist. Add a splash more milk if the batter feels stiff before baking.