This recipe requires bitter almonds. Bitter almonds are poisonous if eaten raw but baking destroys the toxins and produces a more concentrated flavour. If bitter almonds are unavailable, then ordinary almonds will suffice. The Story: Roal Dahl: (...) Like "krokaan" and "riskrem", "kransekake" (pronounced 'kranserkaker') is a totally Norwegian food, which every Norwegian man, woman and child knows as well as the British know baked beans and sausages. Happily, it is a good deal more subtle than either of those bland old British stand-bys. It is, in fact, a magnificent many-tiered cake made of ring upon ring of wonderful macaroon-like biscuit, and no self-respecting Norwegian house is without a kransekake on the table for the Christmas feast. At Easter they do it all over again, except that the kransekake is turned upside-down to make a basket, and one of the larger rings is broken in two to form handles for the basket. Over there they love their kransekake so much that it has become a sort of national symbol, which they bedeck with Norwegian flags on these festive occasions (...). A kransekake is obviously a bit of trouble to make, but in Norway every mother, sweetheart and cook thinks that the trouble is well worthwhile, and with this I heartily agree. It isn't only the actual taste that is so seductive; it is the aura of grandness this great towering cake gives to the table that makes it so splendid.(...) The Recipe: Preheat the oven to 400 oF / 200 oC. Oil the kransekake moulds if you are lucky enough to have them; don't worry if they are not available. Sieve the icing sugar and potato flour into a bowl with the ground almonds. Very lightly whisk the egg whites until fluffy and mix into the dry ingredients. Knead to a soft but firm dough. Pipe into the moulds or roll the mixture into 0.625-in.-thick ropes on a worktop lightly dusted with icing sugar. The small rope should be 5.5 in. long and the next 1 in. longer and so on. Make approx 14-15 ropes. Join the ropes into rings and place on an oiled baking tray, allowing plenty of room for expansion. Bake in oven for 8-10 minutes until crisp and golden. Leave to cool completely before removing. To assemble, sieve the icing sugar into a bowl. Add the egg white and beat until smooth. Make a greaseproof piping bag and fill with some of the icing. Snip off the point of the bag. Pipe icing on top of the largest ring and stick the next sized ring on top. Continue sticking the rings together in this way to form a pyramid. Now decorate each ring with a dropped line forming a scalloped effect. Norwegians decorate the kransekake with Norwegian flags and red ribbons tied into bows at Christmas, and with flowers and eggs at Easter.