Combine peppercorns, anise, cloves and fennel seeds in a small skillet. Toss over medium heat about two minutes to toast lightly. Grind in a coffee grinder or use a mortar and pestle. Add the ground cinnamon. Keep in a sealed container.
Preheat oven to 375 degrees F.
Brush tenderloins with soy sauce. Sprinkle with five spice powder and grated ginger.
Heat a large skillet on medium setting and add oil. When pan is hot add the pork and sear on all sides about three minutes. Remove from heat and transfer pork to a roasting pan. Finish cooking in the oven for about 15 minutes until done to your liking but still juicy.