Béarnaise Sauce
Instantly elevating any dish, this classic Béarnaise Sauce is flavoured with tarragon, dry vermouth, and chervil.
Introduction
Béarnaise used to be as terrifying to prepare as mayonnaise, but now… it’s as preposterously easy. I don’t even bother with clarifying butter any more, I just buy tinned ghee from my local Indian supermarket. It lasts forever and has a subtly stronger ‘brown butter’ flavour, which is no bad thing.
Ingredients
| 260g (9½oz) | butter or ghee |
| 1 | tarragon sprig |
| 1 | shallot, roughly chopped |
| 60ml (2fl oz) | white wine vinegar |
| 120ml (4fl oz) | dry vermouth |
| 10 | black peppercorns |
| 5g (¼oz) | chervil, chopped (or a big pinch of dried chervil) |
| 2 | large egg yolks |
| sea salt and freshly ground black pepper |
Essential kit
You will need a hand-held blender and a jug, cup or jar which the head of your blender fits right to the bottom.
Method
Put the butter or ghee into a saucepan over a very low heat. We need it to melt and sit at around 105°C (220°F).
Separate and reserve a few leaves of the tarragon, then roughly chop the rest, stalks and all. Place in a saucepan with the shallot and pour over the vinegar. Heat until the initial pungency of the vinegar has dissipated, then pour in the vermouth.
Add the peppercorns and chervil, then reduce to about a teaspoonful of liquid.
Find a jug, cup or jar into which the head of your blender fits right to the bottom. For me, that’s a 450ml (15fl oz) Kilner jar. Measure 250ml (8¾fl oz) water into your jar and mark the level with tape or a Sharpie. Pour out the water.
Strain into the marked jar.
Allow the vermouth mixture to cool for a couple of minutes, then add the egg yolks.
Now, pour the clarified butter into the jar up to the line. Try to keep the milky liquid in the pan but it doesn’t matter if a little splashes in.
Blend with a hand-held blender until emulsified, then taste and adjust the seasoning if necessary. Finely chop the remaining tarragon leaves and add to the sauce.
Serve immediately or store the sauce either in a Thermos or in a squeezy bottle placed in a warm water bath. The egg is cooked by the hot butter but it’s never safe to reheat béarnaise or to hold it for more than 2 hours.
