NOTE: I recently remade this recipe and the sauce was too thick for me. I don't know if eggs are getting bigger, or if I'm buying bigger ones, or what. Anyhow, I am now recommending 5 egg yolks from large-sized eggs (not extra large and not jumbo). The sauce was nice and thick but still a bit pourable. And, the leftovers set up into spreadable hollandaise, which I love on a toasted English muffin for a quick treat!