Actually, I forgot to post my findings in the Bavarian cook book. It includes a step similar to that in my earlier post where theu pretzels are put into a Lye[/url:1ha1ap3a] (which is sodium hydroxide and has some interesting other uses!), but in the authentic German recipe case they use Natron[/url:1ha1ap3a]. While this may be hard to come by, I read that you could just use 2 tbsp of baking soda in a litre of water. Not quite the same thing, but easy to get. The recipe says to have the water simmering and to dip the pretzel for 30 seconds. I'll post the Bavarian recipe if anyone wants. Can't remember how or if it was different to that one above, but I'd love to try it as my son loves Bretzeln, but they are not so common up in this part of Germany.