Place fennel and coriander in a spice or coffee grinder; process until coarsely ground. Place spice mixture in a blender or food processor. Add 2 tablespoons broth, Worcestershire sauce, garlic, salt, and pepper; process until well-blended.
Slice the pork tenderloin horizontally into 2 equal pieces. Slice each piece of pork lengthwise, cutting to, but not through, other side; open flat. Rub spice mixture over pork.
Heat olive oil in a large nonstick skillet over medium heat. Add pork; cook 5 minutes on each side or until done. Remove pork from pan; keep warm. Add 1/4 cup broth to pan, and cook until liquid almost evaporates, scraping the pan to loosen browned bits. Pour over pork.