There are several ways to make this sauce but the following way, I find, works best. Just be careful not to add too much heat to the bowl as the eggs can have a tendency to scramble.
- 3 egg yolks
- 1/2 teaspoon of white wine vinegar
- 100 g butter (melted and cooled)
- 1 tsp fresh tarragon (chopped)
- 1 small shallot (very finely diced)
- Have a pot of water simmering on the cooker.
- In a separate bowl infuse the chopped shallot with the white wine vinegar and place over the heat for a minute or two.
- Add the egg yolks and whisk continuously until the colour lightens and the mixture thickens-it should take about 5 minutes.
- You need to keep whisking the mixture and taking it on and off the heat as required so as to prevent scrambling.
- At this stage slowly add in the melted butter-at all times whisking continuously. Taste the sauce, correct the seasoning and add in some freshly chopped tarragon to taste.
- Serve immediately or keep warm in a china teapot or Pyrex jug set in simmering water.