How to make
Put the butter in a deep saucepan and melt it.
The flour is added to it, while stirring at all times.
Once it acquires a golden color, the mixture is diluted with warm fish broth.
Boil the sauce until it thickens (about 5-6 minutes). Season it with salt and freshly ground black pepper.
Once it thickens, it is pulled away from the hob and it is strained.
In another bowl, beat the egg yolks and lemon juice. While stirring at all times, add a little by little of the warm sauce to them.
Once the temperature of the yolks is equalized, they are poured into the sauce and it is stirred again.
The Normande Sauce is suitable for different types of fish.