Originally Posted by medtran49
Umm, mayo can be made with melted butter by itself or in combo with oil. The butter is just not HOT when you make the emulsion. And if I remember correctly, since you are all about traditional/classical, isn't classic Hollandaise made with clarified butter, which is essentially oil?
Clarified butter comes from a cow originally in the form of cream. All other oils come from plants. Big difference.
'Larousse Gastronomique': "Hollandaise sauce is the name of a hot sauce made with egg yolks and butter".
"Mayonnaise is a cold sauce which the basic ingredients are egg yolks and oil blended into an emulsion".
I've been home cooking and professionally cooking for over fifty years. I've never seen a recipe calling for the use of butter in a classic mayonnaise.
As someone mentioned you can make mayo and or Hollandaise from motor oil.