Whip the cream till stiff and put to one side. To make the ricotta filling, mix together the ricotta, candied peel, chocolate chips, hazelnuts, caster sugar, vanilla essence and orange zest in a bowl, and then fold in1/2 of the whipped cream. The remaining whipped cream will be used to decorate the finished cassata. Put the ricotta filling in the fridge to chill while you prepare the sponge. Slice the 3 sponges into thin slices. Use some of the sliced sponge to line the pudding bowl completely. Spread 1/3 of the ricotta filling into the base of the pudding bowl which is lined with the sponge. This will form the first layer. Spread out, and then cover the ricotta filling with a layer of the sliced sponge. Spread ½ of the remaining ricotta filling on top, spread out and then cover with another layer of sliced sponge. Add the remaining ricotta, and spread out. Cover the top with the remaining sliced sponge so that the bowl is filled to the top. You should now have 3 layers of ricotta filling. Place the filled pudding basin in the fridge and chill for 1 hour for the ricotta to firm up. Now all that is left to do is decorate the cassata. Take the chilled cassata out of the fridge and tip it out on to your serving plate. Put the apricot jam into a small saucepan and heat till soft. Brush the warm apricot jam all over the outer sponge layer as this will help stick the marzipan to the cassata. Dust a work surface with icing sugar, and roll out the marzipan to a large circle, and place on top of the cassatella, covering completely. Use your hands to smooth out the marzipan, and then cut off any excess. Put the remaining whipped cream in a piping bag fitted with a star nozzle, and pipe shells around the bottom of the cassata. Finish off the cassata Siciliana with some glace` cherries and toasted almonds.