Preheat oven to 500°F (260°C).
Heat olive oil in an oven-safe skillet on the stove on medium-high heat.
Sear the pork tenderloin for 2–3 minutes per side until a golden-brown crust forms.
Insert an oven-safe probe thermometer into the pork tenderloin, and place the skillet in the oven for 5 minutes.
Turn off the oven (do not open the door) and monitor the internal temperature of the pork. Remove from oven when it reaches 145°F (~63°C). This slow finish ensures juicy, tender pork every time.
Let rest for 3-5 minutes, slice into medallions, and serve.