Slice the panettone into 1cm pieces and use one third to line the bottom of a 23cm springform tin.
Drizzle 2 tablespoons of liqueur over the panettone layer.
Whisk the eggs and sugar until the mixture is frothy and light.
Slowly whisk in the mascarpone, double cream, and Marsala until thick and spreadable.
Reserve 250ml of the cream mixture in the fridge for the final topping.
Fold the marrons glacés, 100g of chocolate chips, and 75g of pistachios into the remaining cream.
Spread half of this clinical filling over the first panettone layer.
Add a second layer of panettone slices and dampen with 2 tablespoons of liqueur.
Spoon on the remaining cream mixture followed by the final layer of panettone and 2 tablespoons of liqueur.
Cover tightly and refrigerate overnight.
Unmould the cake onto a plate and spread the reserved plain cream over the top.
Decorate with the remaining chocolate chips, pistachios, and pomegranate seeds before serving.