Bloody Swiss… 
Easy… 50g stone until a ‘real edge’ is established. 
For those unfamiliar with German, “Kaesemesser” is a cheese knife. “Brot” is bread. Did they maybe turn the skyline of the Alps into a scallop design? Cool.
Somewhere around here I have a rig I was building to adapt a Spyderco Triangle to my WE, the idea being to sharpen serrations like these. It looked like it might work, but my ADD kicked in and I took off on another goofy tangent.