Butter sauce

6 tablespoons white wine
1 twig rosemary
3 yolks
200 gr. butter
1/2 lemon juice
1 pinch white pepper
1/2 teaspoon salt
1 tablespoon hot water

1. Boil the wine with the rosemary until it extinguishes and approximately two tablespoons have remained, remove the rosemary and leave the liquid to cool. Once the liquid cools beat it with the yolks in a mixer until it whitens. Then warm it in the lowest temperature and add the butter in flakes. Make sure the sauce is smooth before you add the rest of the butter.
2. Add flavour to the sauce with some lemon juice, pepper and salt and add hot water to stabilize it.