Austrian Chestnut Cake 4

This is my first instructable. And my first attempt to actually write down one of my cake recipes - for years I've made cakes by rule of thumb (and never quite remembering the complete list of ingredients); now my friends and family have managed to persuade me to put it on"paper".Generally I prefer light cake (ie without chocolate) and then coat it with dark icing (usually chocolate)....so here goes ;-)INGREDIENTS:- chestnuts (roasted/cooked) 250gramm- powder sugar 200g- butter 30g- eggs (separated yolk/white) 4- flour 60g- rum/brandy 2TSP- baking powder 5g- citrus peel^ of about 1/4 lemon/orange- vanilla sugar^ 1TSP >for the icing: plum preserve, rum^, sugar, butter, chocolate.[the ^ marked ingredients are optional]