Add steak to pan, and cook 5 minutes on each side or until desired degree of doneness.
Transfer steak to a cutting board; let stand 5 minutes.
Cut across grain into thin slices.
Add garlic and shallot to pan; saut 1 1/2 minutes or until lightly browned.
Add vinegar, and cook 1 1/2 minutes or until liquid almost evaporates.
Add tomatoes, 1/4 cup basil, 1/4 cup green onions, and remaining 1/4 teaspoon pepper. Cook 2 minutes or until the tomatoes soften and begin to release their liquid, stirring occasionally.
Serve tomato mixture over sliced steak.
Sprinkle with remaining basil and remaining green onions.