Chef John’s Butterless Bearnaise Sauce
Egg yolks are used to thicken a non-butter version of the traditional bearnaise sauce, which is then flavored with tarragon and Dijon mustard.
In a metal mixing bowl or small saucepan, whisk together the egg yolks, black pepper, tarragon, Dijon mustard, tarragon vinegar, water, and salt.
Place over low heat and whisk for 1 to 2 minutes, or until mixture foams and small wisps of steam come from the sauce.
To increase or decrease heat, raise and lower the pan over the heat