How to Make It
Heat both olive oils in a small saucepan over low to 120°F.
Combine yolks, 3 tablespoons warm water, lemon juice, salt, white pepper, sugar, and cayenne in a blender. Pulse until combined. Pour heated oil into a spouted measuring cup.
With blender running, slowly add oil in a thin, steady stream. If sauce is too thick, add up to 2 tablespoons warm water, 1 tablespoon at a time, and process until desired consistency is reached.