makes 1/2 cup
Add the chicken stock to a pot and place it on the stove on high heat. Bring to a boil and reduce the heat to a simmer.
Wait for the moment the stock has reduced to at least 3/4.
Once you reach the stage where the stock has thickened, add cream while stirring with a whisk.
Bring the stock with the cream to a boil and reduce again for 1-2 minutes. Now add the butter cubes and whisk rapidly until well emulsified.
Finally, adjust the seasoning with lemon juice and add salt if needed.
If the sauce is not thick enough, reduce a bit further.