Melt <quantity>300<unit>g</unit></quantity> of unsalted butter over low heat

Set the melted butter aside until the milk proteins sink to the bottom of the pot

Pick <quantity>1<unit>bunch</unit></quantity> of basil flowers

Gently pour the melted butter into another recipient, being careful not to mix it back with the milk solids

Add the picked basil flowers and the melted butter to a blender

Blend on high speed until homogeneous

Sieve the mixture

Fill a small saucepan with water and bring it to a boil

Remove the saucepan from the stove and place a large heatproof bowl on top of it. Add <quantity>20<unit>ml</unit></quantity> of white wine vinegar

Add <quantity>3</quantity> egg yolks to the bowl. If you’re using whole eggs, save the whites for other preparations

Pour the herb butter into the bowl, in a thin stream, while constantly whisking. Continue until it is emulsified

Season with salt to taste

Keep whisking and immediately remove from the heat when the sauce thickens. The herb hollandaise is ready

Grab some grilled fish or poached egg, and enjoy!