Bernaise sauce

It is a warm emulsion of egg yolks and butter, flavoured with a reduction of vinegar, shallot, tarragon and peppercorns. It is closely related to hollandaise, but tarragon gives it its distinctive savoury, anise-like flavour.

Whisk egg yolks with the strained vinegar reduction over a pan of gently simmering water, then add warm melted butter a little at a time while whisking constantly. Keep the bowl above the water, not touching it, and take it off the heat once the sauce is thick enough to coat a spoon.

Whisk a teaspoon of cold water in a clean bowl, then slowly whisk the split sauce into it, a spoonful at a time. If it is simply too thick, whisk in a few drops of warm water.

It is a classic partner for grilled or pan-fried steak, especially steak frites, and also goes well with roast beef, grilled vegetables and eggs. Spoon it on just before serving rather than cooking it with the food.

It is best made just before serving; butter-based sauce can thicken or split as it cools. Refrigerate leftovers promptly in a covered container and use within a day; warm gently over simmering water while whisking, without letting it boil.

Use hollandaise for a similarly rich, buttery sauce, though it has a lemony flavour rather than Bernaise’s tarragon and shallot notes. For a lighter, tangier option, try a spoonful of mustard stirred into thick yoghurt.

A small serving of about two tablespoons is enough to dress a steak without overwhelming it. That amount provides 152 kcal.