You will need:
- 3 large organic egg yolks
- 2 tablespoons of freshly squeezed lemon juice
- 50g of salted Lurpak butter, at room temperature
- 1 teaspoon of white vinegar
- 1 teaspoon of water
- pinch of salt
In a bain marie or double-boiler (glass bowl set just above simmering water), add the egg yolks and 1 tablespoon of lemon juice.
Using a small whisk, beat the yolks and lemon together until they form a sabayon. This happens when the lemon juice emulsifies the egg yolks and they thicken and take on a lighter hue.
To know when you’ve reached this point, the mixture should cling to the whisk and you should be able to see the bottom of the glass bowl when you drag your whisk through it.
The mixture should still be amorphous but if it gets too thick, add a little more lemon juice and whisk.
Once you have reached your sabayon stage, add in your butter, a small amount at a time, and continue whisking until it has melted and combined into the egg yolks.
Whisk in all the butter, adding the white vinegar – this gives the Hollandaise a lovely light colour and a tangy flavour.
Remember to keep the water under your bain marie gently warmed but not boiling or simmering to ensure that you don’t end up with scrambled eggs. If your sauce is getting too hot and clumping, simply remove from the heat and add a touch of water to dilute.
The trick with Hollandaise is timing, but to keep the finished sauce fresh, remove from the heat and place a piece of clingfilm directly onto the top of the sauce to prevent it from forming a skin.
To reheat, simply place back over the simmering water (I use the leftover water from the poaching pan – see below) and whisk until smooth and silky again.