Béarnaise Sauce

Instructions

1. Prepare the reduction
   In a small saucepan, combine the white wine vinegar, white wine, shallots, half of the tarragon, and crushed peppercorns. Bring to a simmer over medium heat and reduce until only about 2 tablespoons of liquid remain, about 5 minutes. Strain and set aside to cool slightly.
2. Set up a double boiler
   Fill a medium saucepan with about 2 inches of water and bring to a gentle simmer. Place a heatproof glass or metal bowl on top, making sure the bottom doesn't touch the water.
3. Create the emulsion
   In the bowl of the double boiler, whisk the egg yolks with 1 tablespoon of cold water and the cooled reduction. Continue whisking vigorously over the simmering water until the mixture becomes pale and thickens enough to leave a ribbon trail when the whisk is lifted, about 3-4 minutes. Be careful not to let the eggs get too hot or they will scramble.
4. Incorporate the butter
   Remove the bowl from the heat. Slowly drizzle in the warm melted butter in a thin stream while whisking constantly, creating a smooth emulsion. Start with just a few drops, then add the rest in a steady stream, continuing to whisk. The sauce should thicken to the consistency of hollandaise.
5. Season and finish
   Stir in the remaining fresh tarragon, chervil, lemon juice, salt, and cayenne pepper (if using). Taste and adjust seasoning if needed. If the sauce is too thick, whisk in a few drops of warm water until desired consistency is reached.
6. Serve immediately
   Béarnaise sauce should be served warm. It pairs perfectly with grilled steak, roasted beef, poached eggs, or steamed vegetables. If not using right away, keep warm in a thermos or over a pan of warm (not hot) water for up to 1 hour.