Season both sides of the filet mignon with salt and pepper. Allow to sit at room temperature for 30 minutes.
12 oz filet mignon, 1 teaspoon kosher salt, 1 teaspoon black pepper
Preheat the grill or grill pan to medium high heat, or preheat your oven to broil (500 degrees).
Place steaks on the grill and cook for 3-4 minutes on each side for medium rare. Place steaks on a plate and cover with foil.
In a small saucepan, add the olive oil over medium high heat. Once shimmering, add in the shallot and cook, stirring frequently for 2-3 minutes or until softened.
1 teaspoon olive oil, 1 tablespoon shallot
Add in the Worcestershire sauce and beef broth and bring to a simmer. Meanwhile, whisk together the water and cornstarch into a slurry.
1 tablespoon Worcestershire sauce, ¼ cup beef broth, 1 tablespoon cornstarch, 2 tablespoon water
Once mixture is simmering, add in the slurry mixture, whisking constantly until slightly thickened. Remove from the heat and stir in chocolate, stirring until fully melted.
1 oz. dark chocolate
Plate steaks and serve chocolate sauce on top.