• Two egg yolks
• A big bunch of tarragon, finely chopped, stalks and leaves separated
• One shallot, finely sliced
• About 200ml of white wine vinegar
• 1 tsp hot German mustard
• 6 black peppercorns
• Decent olive oil
• Salt
• Black pepper

In a small saucepan, combine the vinegar, the shallot, the bottom stalky third of the tarragon and the black peppercorns. Bring to a gentle simmer and reduce by half. Strain.

In a metal bowl, combine the egg yolks and the mustard. Set a small saucepan of water to simmer, place the metal bowl over the simmering water. Whisk, drizzling in about three tbsp of the vinegar reduction. Keep whisking as you drizzle in olive oil – around three tbsp of this, too – until you have a thick, warm sauce. Taste, adjust the seasoning, whisk in the rest of the tarragon. Turn off the heat and keep it moving every few minutes. If it gets too thick, whisk in a little water and vinegar reduction until you’ve got the right consistency.

Adjust for final seasoning before serving in little bowls with a teaspoon each – some people lose their minds when confronted with bearnaise.