coating:
preheat oven to 190˚C.
grease and line a cake tin.
whisk together the butter and 115g sugar until fluffy.
add egg yolks, orange rind, ricotta, flour and walnuts and combine well.
whisk egg whites until stiff. whisk in 35g sugar.
gradually fold the egg whites into the mixture.
bake for about 30 minutes.
when cooled, transfer on a plate.
in a small saucepan, heat the jam with 1 tbsp water, press through a sieve and add the brandy. use to coat the cake.
finish with chocolate shavings.