Gently melt the butter either in a pan, allowing the milky white liquid to fall to the bottom of the pan, or in a covered plastic container in the microwave. If you then chill it at this stage it makes it easy to pour away the separated impurities.

When you are ready to make the sauce, gently melt and warm through the butter, it should be perfectly clarified by now.

Put the vinegar, peppercorns, bayleaf, thyme and tarragon into a small saucepan and bring to a rapid boil and reduce to about 1 tbsp of liquid is left, remove from heat and strain off.

Put the egg yolks and vinegar in a heatproof bowl over a pan of simmering water and whisk until it all becomes light and foamy and starts to look like a sauce, be careful not to scramble the eggs at this stage by getting the bowl too hot. Either turn the heat off or remove the bowl for a minute if its going too quickly.

Add the clarified butter, a little at a time, whisking well with each addition, be patient and don’t try to add too much in one go or you may split it, if it starts to get too thick either add a little more vinegar reduction or a splash of warm water, then continue to add the butter until all is used. Once you have a perfect consistency of sauce that will hold if you spooned it over something, then season with a little salt and pepper and lemon juice to taste.