Preheat grill or broiler.
Combine first 7 ingredients in a large zip-top plastic bag. Add steak; seal bag. Marinate in refrigerator 20 minutes, turning once. Remove steak from bag, reserving marinade.
Place steak on grill rack or broiler pan coated with cooking spray; cook 6 minutes on each side or until desired degree of doneness. Let stand 5 minutes. Cut steak diagonally across grain into thin slices; keep warm.
While steak cooks, combine reserved marinade, tomato paste, and mustard in a medium saucepan over medium-high heat, stirring well with a whisk. Bring to a boil, and cook until reduced to 1 cup (about 7 minutes). Serve the sauce with steak.