Tyrolean Bozner Sauce - cooking recipe

Ingredients

4 hardboiled egg
1 -2 tablespoon Dijon mustard (to taste)
salt and pepper
vegetable oil
1 teaspoon white wine vinegar
fresh squeezed lemon juice (the juice from 1/4 to 1/2 of a lemon, to taste)
1/4 cup finely chopped fresh chives (or less, to taste)

Preparation

Peel the cooled hardboiled eggs and separate the egg whites from the yolks.
Press the yolks through a fine mesh strainer into a medium bowl. Combine the yolks with a tablespoon of mustard (I use Dijon); season to taste with salt and pepper. Drizzle about 2/3 to 3/4 cup of vegetable oil in a continuous stream, whisking all the while, until sauce is smooth, thick and velvety.
Whisk in 1 teaspoon of vinegar and the juice from 1/4 to 1/2 of a lemon (again, to taste).
Finely chop the egg whites and whisk them into the sauce. Whisk in about 1/4 cup (or less) of finely chopped fresh chives.