Why - if I could think of a clear/obvious abbreviation for recipe, I would, but I don't think you could make it much shorter without losing clarity.  However, in the case of Protot(type), I think the abbreviation is fairly clear (I guess it could mean protocol).  How about changing RegisterProto and RegisterRecipe to AddRecipe and AddPrototype? - that is probably better since Register sort of implies the listener pattern which this is not.