Hollandaise sauce

Needing a cheats Hollandaise sauce recipe that stays stable and maybe can be prepared in advance and warmed over Bain Marie . I heard that Xanthan gum can be added as a stabiliser . Please give me a recipe if you have one and where I can get this xanthan gum if it’s a good idea! Eggs Benni is always super popular at my B&B so it would be a great help if I could simplify the hollandaise bit .