01 -
Set a small pan over medium heat and toss in the butter. When it's fully melted, stir in the beef stock, cream, mustard, crushed pepper, and salt.
02 -
While stirring often, let the sauce simmer for around 5-10 minutes. When it clings to a spoon without dripping, take the pan off the heat.
03 -
Pour the sauce directly over your dish or put it in a small serving bowl.