Another classical French sauce that is excellent on grilled filet mignon or roast tenderloin of beef. It is also good on most types of fish including salmon, rockfish and halibut. I find this sauce goes particularly well with steamed broccoli and asparagus.
½ cup white wine
1 T. chopped shallots or green onions
½ tsp. crushed dried tarragon (or 1 tsp. fresh)
½ tsp. chopped parsley
3/4 cup warm melted butter
3 egg yolks
Begin by making a tea of the white wine, tarragon, shallots, and parsley. Reduce to half volume over low heat. Strain the tea and use all of this liquid as you would to make Hollandaise sauce, adding it to the egg yolks, whisking constantly. Finally add the butter very slowly while whisking until the sauce has thickened.