Start by melting 1 tablespoon of butter in a pan over medium heat.
Sauté the minced shallots in the pan until they become translucent.
Add minced garlic and cook for another half minute.
Pour the sherry wine into the pan and stir it. Let it simmer for 3 to 5 minutes until the liquid thickens and reduces by half.
Add chicken or vegetable stock and heavy cream. Stir them and let the mixture simmer.
Add Dijon mustard and chopped herbs. Let them simmer more, like 5 to 7 minutes.
Season the sauce with salt and ground black pepper.
Strain the sauce to get a smooth texture.
Add another tablespoon of butter to add some richness.
