Heat butter or oil in a saucepan over medium heat.
Add shallots and cook until soft, then add garlic and sauté briefly.
Stir in crushed peppercorns and cook for 30 seconds.
Pour in beef broth (and optional brandy), scraping the pan to deglaze.
Simmer for 4–5 minutes until slightly reduced.
Lower heat and add heavy cream, stirring continuously.
Simmer gently until the sauce thickens and coats a spoon.
Season with salt and optional Worcestershire or mustard.
Serve warm over steak, chicken, or vegetables.
