If you ask a purist about Hollandaise Sauce, the word "blender" never comes up. I have found this method to make the smoothest and most stable Hollandaise Sauce ever. If you make more than you need, you can store it in the refrigerator for up to 6 months. The sauce is named after Holland, where it was introduced by the Huguenots, French Protestants who fled religious persecution in the 16th and 17th centuries.