1/4 cup Tarragon white wine vinegar
1/4 cup Dry white wine
2 TB Shallots, minced
1 1/2 TB Chervil, Chopped (Substitute: 1 TB Celery Leaves, 1 tsp Italian Parsley, 1/4 tsp Fennel or Anise Seeds, crushed)
1/4 tsp Black Peppercorns, crushed
Pinch of Cayenne pepper
1/4 cup Egg Yolk
3/4 cup Clarified Butter
2 1/2 TB Fresh Tarragon Leaves, Chopped Fine; Divided
In a small saucepan, combine Tarragon vinegar, white wine, shallots, 1/2 TB Tarragon, Chervil, 1/4 tsp salt, and peppercorns over medium heat.
Bring the mixture to a to a boil then reduce heat and simmer until the liquid is reduced to 3 TB.
Strain into a bowl and let cool slightly.
In the top of a double boiler, whisk egg yolks with the reduction, a pinch of salt, and a pinch of cayenne until the yolks become thick and pale.
Place the bowl over barely simmering water and continue whisking until the mixture becomes smooth, creamy and thick enough to leave a clear line in the bottom of the bowl when the whisk is drawn through.
Do not heat the yolk mixture too much or you will end up with scrambled eggs; the proteins will re-bond with each other if the yolks get too hot.
Begin drizzling in the butter a little at a time, continuing to whisk until each addition emulsifies.
Once all the butter has been added, stir in the tarragon and serve.
Place in a thermal carafe to keep warm.
Pairs Well With
Béarnaise and Hollandaise are sister sauces being both emulsions of butter in egg yolk and acid. The only real difference between the two is the acid used. Hollandaise uses lemon; béarnaise uses vinegar and/or white wine. The method of construction however, is identical.