Set sous vide machine to 60C/140F.
Season pork lightly with salt or a seasoning of your choice. Place tenderloin in sous vide bag and remove the air through a vacuum sealer or the displacement method. Drop the bag in the bath for two hours.
Remove bag from bath. Take pork tenderloin out of the bag, pat dry with paper towels and season with salt and pepper (or seasoning) to taste.
Heat up large skillet on high and add oil. Sear pork tenderloin for 1 to 2 minutes on each side. Remove from pan, and place on a plate to rest for 5 minutes. Once rested, serve and enjoy! Alternatively sear the tenderloin on a grill or using a searing torch.