You make a good point, Andrea. German recipes often vary from region to region. If you are from the Allgäu region, yes, you’ll be used to using Bergkäse (mountain cheese). Where I lived, we use Emmental or sometimes even Gouda. Also, my recipes are written and adapted for a US audience, and I always want to make sure everybody can easily find the ingredients. And I don’t know of any supermarkets that carry Bergkäse here. Emmental is a good choice, but even that can be tough to find, which is why I also suggest Gruyere or even regular Swiss cheese. Hope that makes sense. 🙂