Preheat oven to 400. Place tenderloin on large cutting board. Butterfly (cut nearly in half lengthwise so it folds open like a book). Pound with a meat mallet until even. Season on both sides with salt, pepper, thyme, and rosemary. Move to another surface.
Lay bacon strips alongside each other in a row. Place tenderloin on top and perpendicular to bacon strips. Spoon a half inch layer of stuffing on top of pork, leaving a half inch or so of space at the edges (see pictures in post). Top with arugula.
Roll up pork tenderloin around stuffing. Take each strip of bacon by both ends and wrap it tightly around the tenderloin.
Oil a 9x13 pan, and place the bacon-wrapped stuffed tenderloin (bacon seam side down) into the pan. Cook for 35-40 min, or until an internal temperature of 145 has been reached.
Optional: crisp bacon for an additional 1-2 min on broil setting
Slice into medallions the width of a strip of bacon, and serve. Enjoy!