To make the biscuits, beat the sugar, butter and vanilla together until creamy. Lightly beat in the eggs. Now gently fold in the flours and baking powder until a soft dough is obtained. Turn the dough onto a lightly floured surface & knead gently into a smooth dough. Roll into a thick cigar shape and cut into 1 cm thick disks. Put the discs onto a baking sheet lined with baking paper and bake at 175°c for approximately 15 minutes. Allow to cool completely. Meanwhile, make the butter cream. Beat the butter and icing sugar with the vanilla and citrus zests until, light creamy and fluffy. In a separate, bowl whisk together the egg whites with the castor sugar, until thick. Next, fold in the whites into the butter cream. Chop the cooked biscuits into uneven pieces and put in a large enough mixing bowl. Add the butter cream and the rest of the filling ingredients and combine together. Turn the mixture onto a serving plate and mould into a dome shape. Allow the prinjolata to dry for a couple of hours before decorating. Whisk the egg whites until a stiff peak is formed. Cook the sugar and water over a low heat until it reaches a temperature of 120°c on a sugar thermometer. Carefully, pour the hot sugar over the meringue, whisking constantly. Keep whisking even after the sugar syrup is all poured in, until the meringue has cooled down. Spread the meringue over the prinjolata, drizzle with the chocolate and garnish with the nuts and cherries.