Every time I make hollandaise sauce, it is always a guess whether I will get it right, and doubly so if I try to make Bearnaise. I used to use a blender method, which always worked, but we got rid of our old blender during one move and replaced it with a stick blender. Ever since we’ve done that, I’ve had a hard time getting it just right. The last time I made it (to go with steamed artichokes) it wasn’t thickening right, so I popped it into a saucepan and whisked constantly over medium heat. Rescued it! That was a relief. I just need to keep practicing till I figure out what slight thing I do “wrong”. I think one time I didn’t add the hot butter slow enough or fast enough. Still don’t know which is preferable.