Preparation Add the white wine, white wine vinegar, lemon juice, shallots, salt, pepper, and half of the tarragon leaves, in a saucepan.
Bring to a boil and simmer over medium heat for about 5 minutes, until the mixture is reduced to about 1/4 cup.
Add the mixture to a food processor and allow to cool for a few minutes.
Add the egg yolks and mix for 30 seconds.
Add the butter in a heatproof cup with a pour spout and heat up in the microwave (or heat directly in another saucepan).
Then, with the food processor running, very slowly stream in the hot butter.
Add the remaining tarragon and pulse for 2 seconds.
If the sauce is too thick, add a little more white wine.
Pour directly over steak and asparagus.
Enjoy!