Ingredient

Béarnaise

Béarnaise is hollandaise built on a sharp, aromatic reduction of vinegar, shallot and tarragon instead of plain lemon. That reduction is not a garnish — it is what makes the sauce able to stand up to a steak.

The reduction

White wine vinegar, dry white wine, finely chopped shallot, crushed peppercorns and tarragon stalks are simmered down until only a couple of tablespoons remain. Reducing concentrates the acid and the aromatics and boils off the harshness of raw vinegar.

This is why béarnaise cuts through fat where hollandaise would sit alongside it. Steak is rich and needs acid; the reduction supplies it in a form that tastes cooked rather than sharp.

Strain the reduction, or leave the shallot in for texture — both are done. The tarragon stalks go into the reduction; the chopped leaves go in at the end, where their volatile aroma survives.

Making it

1. Simmer vinegar, wine, shallot, peppercorns and tarragon stalks until reduced to about two tablespoons. Strain if you want it smooth.
2. Whisk the yolks with the cooled reduction over barely simmering water until thick, pale and tripled in volume.
3. Off the heat, trickle in warm clarified butter, whisking constantly.
4. Loosen with a teaspoon of warm water if it gets too thick to move.
5. Stir in plenty of chopped fresh tarragon and a little chervil if you have it. Season with salt and a touch more vinegar if it needs lifting.
6. Hold somewhere barely warm until service.

Keeping it alive during a meal

• A wide-mouthed thermos flask is the domestic answer and holds it perfectly for an hour or two.
• A bowl over a pan of water that has been taken off the heat works, provided the water is not hot enough to keep cooking it.
• Never let it get above hand-hot. Above that the yolk starts to set and the sauce breaks.
• Whisk in a spoonful of warm water if it stiffens while standing.
• Do not refrigerate and reheat. Make it last, and time the steak around it.

The variations

Choron

Béarnaise with tomato purée. Pink, and very good with fish.

Foyot

Béarnaise with a spoonful of reduced meat glaze. Deeply savoury.

Paloise

Mint in place of tarragon. Traditionally with lamb.

Café de Paris

Not a béarnaise but the other great steak butter, and worth knowing as an alternative.

Common mistakes

• Using the vinegar unreduced. Raw vinegar tastes harsh and thin, and the reduction is where the depth comes from.
• Putting the tarragon leaves into the reduction. They boil away to nothing; only the stalks go in there.
• Letting the sabayon get too hot. If the bowl touches the water, or the water boils, the yolks scramble.
• Adding the butter while it is still hot from the pan. Warm, not hot.
• Making it too early. Bearnaise has a working life measured in an hour or two, and no amount of care extends it much further.

Common questions