Get your dry pork tenderloin and make the butterfly cut. Place it in a large bowl and drizzle with oil. Season it with teaspoon of salt and pepper to taste then set aside.

Get a medium bowl and combine orange juice, mustard, brown sugar and rosemary. Set aside.

Heat oil on a large cast-iron skillet over medium-high heat. Transfer pork tenderloin to hot skillet. Cook 5-6 minutes on the first side or until golden brown. Flip and cook on the 2nd side 5 minutes more or until just cooked through. Remove tenderloin from pan and place on rimmed cutting board and lightly cover with foil to keep warm.

Add orange juice mixture to skillet. Add any accumulated meat juices from cutting board then combine cranberry sauce. Stir cranberry sauce and cook until it's reduced by half (2-3 minutes). Remove from heat and whisk in butter just until it melts in the cranberry mixture.

Thinly slice the brown pork and place it on a serving platter.

Place cranberry-orange sauce on top. For a beautiful presentation, garnish it with additional orange zest, fresh rosemary, or some orange slices, if desired. Enjoy!