To prepare relish, cut chiles and bell pepper in half lengthwise; discard seeds and membranes. Place halves, skin sides up, on a foil-lined baking sheet; flatten with hand. Broil 15 minutes or until blackened. Place in a zip-top plastic bag; seal. Let stand 15 minutes. Peel and chop. Combine chiles, bell pepper, and next 6 ingredients (through garlic) in a small bowl; toss well. Set aside.
To prepare steak, combine sugar and next 4 ingredients (through ginger) in a small bowl. Sprinkle steak with sugar mixture. Place steak on a grill rack coated with cooking spray; grill 6 minutes on each side or until desired degree of doneness. Cut steak across grain into thin slices. Serve with relish.