Classic French Hollandaise sauce — the silky emulsion with egg yolks, butter and lemon

Hollandaise sauce, once also known as “Dutch sauce”, is one of the classic sauces of French cuisine: it is made with egg yolks, melted butter and lemon juice, usually seasoned with salt and white pepper or cayenne pepper. Its name was given in honor of the French victory in the Dutch War (1672–1678), during the reign of Louis XIV.

Its secret is the emulsion: the egg yolks are whisked over a bain-marie until they thicken, then the melted butter is added thread by thread while whisking without stopping. The heat must be gentle and controlled — too much heat breaks the sauce and makes it grainy. For this reason the sauce is served immediately, warm, and cannot be reheated.

It is the classic companion of boiled asparagus and Eggs Benedict, but it also goes excellently with grilled fish, steamed vegetables or roasted meat. Other famous sauces are born from Hollandaise, such as Béarnaise — with shallots, tarragon and wine vinegar.

Ingredients (for 4 people, about 250 ml of sauce):

• 3 fresh egg yolks, at room temperature
• 150 g butter, melted and left to cool slightly (warm, not hot)
• 1 tablespoon fresh lemon juice
• 1 tablespoon cold water
• 1/2 teaspoon salt
• White pepper or cayenne pepper, to taste

Preparation:

1. Melt the butter over very low heat and set it aside to cool slightly — it should be warm to the touch, not hot.
2. In a metal bowl, put the egg yolks, water and lemon juice; whisk lightly with a whisk.
3. Place the bowl over a pot of gently simmering water (bain-marie). The bottom of the bowl must not touch the water.
4. Whisk continuously for 3–4 minutes, until the mixture thickens, lightens a little and leaves whisk trails. Caution: if it heats too much, the egg will curdle.
5. Remove the bowl from the heat. Start pouring in the melted butter in a very thin thread, whisking without stopping, until the sauce binds and becomes creamy like mayonnaise.
6. Add the salt and pepper; taste and adjust with a little lemon juice if you want it fresher.
7. Serve immediately, warm.

Tip: If the sauce breaks, whisk a fresh egg yolk in a clean bowl and add the broken sauce thread by thread while whisking vigorously — it will bind again. Do not let it get cold: Hollandaise is eaten warm and does not tolerate reheating.

Preparation time: 15 minutes. Servings: 4.