How to Make It
Lightly coat beef with cooking spray; sprinkle evenly on all sides with pepper and 1 1/2 teaspoons salt. Loosely cover beef with plastic wrap; let stand at room temperature 30 minutes.
Preheat oven to 450°.
Heat a large, heavy skillet over medium-high heat. Coat pan with cooking spray. Add beef to pan; cook 2 minutes on all sides or until browned. Place beef on a broiler pan coated with cooking spray. Bake at 450° for 20 minutes or until a thermometer registers 128° or until desired degree of doneness. Remove from oven; let stand 15 minutes.
Return skillet to medium-high heat; add shallots and butter to pan, scraping pan to loosen browned bits. Cook 1 minute, stirring constantly. Stir in broth, port, jelly, vinegar, thyme, and rosemary; bring to a boil. Cook until reduced to 1 1/2 cups (about 17 minutes). Remove from heat; stir in remaining 1/4 teaspoon salt.
Cut beef crosswise into 16 slices. Serve with sauce.