I would like to make the Simnel Cake, which I have made for the past 2 years. It always turns out well but I would like to know if there is any advantage to making it early to allow it to mature and if so, how far in advance can I make it?
Nigella's Simnel Cake (from FEAST) is a fruit cake that has a marzipan filling and topping. Nowadays it is associated with Easter, though originally it was served on Mothering Sunday in the UK (this year on Sunday 26th March 2017). It is a light fruit cake so it does not need to be made in advance and does not benefit from "maturing" in the way that a rich fruit cake does.
The cake can be made up to a week ahaed but add the marzipan topping the day before serving. Once decorated, keep the cake in an airtight box in a cool place for 5 days. If you want to make the cake further in advance then freeze it without the marzipan topping. There is a small risk that the marzipan filling turns a little sticky when the cake defrosts but this will not affect the taste of the cake. Once the cake is completely cold, wrap it in a double layer of clingfilm and a layer of foil and freeze for up to 3 months. To defrost the cake, unwrap it and leave it on a wire rack for 5-6 hours and only add the marzipan topping once the cake has come to room temperature. For Easter you may also like to consider Nigella's Easter Egg Nest Cake and Hot Cross Buns.