MIX chicken broth and soy sauce; set aside.
COOK and stir broccoli and garlic in hot oil in large skillet on medium-high heat until crisp-tender. Remove from skillet; keep warm.
ADD chicken to skillet; cook and stir 3 to 4 minutes or until cooked through. Add broth mixture; mix well. Bring to boil. Reduce heat to medium-low. Add mustard; mix well. Return broccoli mixture to skillet; mix lightly. Cook until heated through, stirring occasionally.