Cut the beaver patties into strips and let them dry in the oven at 80 degrees for about 1 hour (similar to breadcrumbs). Then grind to a powder in a blender.
Beat egg yolks and sugar in a water bath until frothy, add beaver pancake powder and mix well.
Add the Appenzeller Alpenbitter and fold in the cream, which is not too stiff.
Line a cake tin with cling film, fill in the mixture and put the whole thing in the freezer for at least 4-5 hours (can also be stored for 1-2 weeks).
Let thaw slightly before serving and serve with whipped cream.