1 (1-pound) flank steak, trimmed |
1/4 teaspoon salt |
1/4 teaspoon black pepper |
cooking spray |
1 cup cubed peeled cucumber |
1/2 cup grape or cherry tomato halves |
1/4 cup thinly sliced shallots |
1 tablespoon chopped fresh mint |
1 tablespoon chopped fresh basil |
1 tablespoon chopped fresh cilantro |
2 tablespoons brown sugar |
3 tablespoons low-sodium soy sauce |
2 tablespoons fresh lime juice |
1/2 teaspoon crushed red pepper |
6 (10-inch) flour tortillas |
12 bibb lettuce leaves |