In reply to cb294:
We squeeze the oranges into the wine and then chuck the segments into the pot for good measure, giving the Glühwein flavour from both the juice and the skin. Our recipe doesn't include cardamom but does include whole Piment, cinnamon and cloves. That said, I did wonder whether cardamom would go nicely with the recipe - it fits in with my understanding of spices. I'll definitely try it, next time round.
Our recipe comes from South African. I haven't used it since I left, until last week. We did realise that SA wine is a lot dryer than the red wine we found at Rewe - we used to add sugar to the SA wine but adding sugar to the wine we bought in Germany made it far too sweet. Tasty, but too sweet. (This might also be a symptom of a change in our own tastes, since we have become fans of the German bakeries who make slices piled inches-high with cherries and somehow more "fruity" than "sweet".)
Luckily, we have the whole of winter to perfect our technique. By Christmas, we'll be experts.
Zwiebelkuchen? Das kenne ich noch nicht!