Prepare the pan by adding steak grease or bacon grease to the bottom.

Sauté minced shallots and garlic in the grease for 1-2 minutes until softened.

Deglaze the pan with cognac, scraping up any browned bits.

Add beef broth and crushed black peppercorns to the pan and bring to a boil.

In a separate bowl, combine heavy cream and cornstarch, mixing well.

Whisk the cornstarch mixture into the sauce and simmer until the gravy thickens to your desired consistency.

Whisk in Dijon mustard and pour any remaining steak juices from the plate into the pan to enrich the gravy.