Sprinkle the cracked pepper over the tenderloin and rub it in.
Heat a large skillet over medium-high heat and add the butter. When the butter is melted, add the tenderloin and cook for 5 minutes, turning to cook each side.
Transfer the tenderloin to a baking dish and bake for 15 minutes, or until the internal temperature reaches 140°F. Remove from oven and let rest for 5 minutes.
In the same skillet used to cook the tenderloin, add the port and bring to a boil. Reduce the heat and simmer for 5 minutes.
Add the chocolate chips and stir until melted. Remove from heat and season with salt to taste.
Slice the tenderloin and serve with the chocolate port sauce.
Interesting Facts
Beef tenderloin is the most tender cut of beef.
The port used in the sauce is a fortified wine.
Dark chocolate contains flavonoids, which have antioxidant properties.