A standard! This is used in many recipes: eggs Benedict being one of them.
Cook this in the thickest pot you have. The challenge is to thicken without over cooking/ curdling so be carefull and do not leave it!
If you need to keep it warm, do so in a double boiler over simmering water to prevent overheating.
Place small pan/pot (enamelled cast iron is good) on low heat.
Mix all ingredients.
Stir constantly until the sauce thickens.
Remove from heat as soon as it does.
Should you overdo it and the sauce starts to curdle, quickly add 1 tablespoon of ice water and stir.
And if that is not enough add one more egg yolk and stir over very low heat.
2 servings