Gather all ingredients before starting the recipe.
Season 1 petit filet with kosher salt and freshly ground black pepper one hour before cooking and allow to come to room temperature.
Heat a small skilet over medium high to high heat for about 2 minutes, then add 1 tbsp butter and the 1 petit filet. Sear without moving for 3 minutes. Flip and sear for another 2-3 minutes. To test, either insert a meat thermometer (130-135℉) or press down on the center of the filet. If it seems firm but not hard, the filet should be medium rare.
Remove filet from skillet to a plate and allow it to rest for 5-7 minutes.
Prepare Peppercorn Sauce while the filet is resting.