1In 2-quart saucepan, heat oil over medium-high heat. Add onion; cook about 2 minutes, stirring frequently, until crisp-tender.
2Stir in broth, water, Italian seasoning, frozen broccoli in cheese sauce and tortellini. Heat to boiling, stirring occasionally and breaking up broccoli.
3Stir in chicken. Cook about 4 minutes, stirring occasionally, until tortellini are tender. Stir in tomato. Top each serving with 1 tablespoon cheese.