Add egg yolks and mustard to a bowl and whisk to combine. Blend in a circular motion with an immersion blender and slowly add the oil, taking care for the first 30 seconds to avoid splitting.
Add the rest of the oil until you have a thick, glossy mayonnaise. Add lemon juice (start with juice of 1 lemon and work up from there), salt and pepper, then blend a little more and serve. |