PREPARATION:

1. Place chicken broth and oil in small saucepan; bring to a boil over high heat. Stir in couscous; cover. Remove saucepan from heat; let stand 5 minutes.
2. Cut thin slice from top of each tomato. Remove pulp, leaving 1/8-inch-thick shell; reserve pulp. Place tomatoes, cut sides down, on paper towels to drain. Meanwhile, drain excess liquid from reserved pulp. Chop pulp to measure 2/3 cup.
3. Spray large nonstick skillet with cooking spray; heat over medium heat until hot. Add zucchini, onions and garlic. Cook and stir 5 minutes or until vegetables are tender.
4. Combine couscous, reserved tomato pulp, vegetables, parsley, mustard and Italian seasoning in large bowl. Fill tomato shells evenly with couscous mixture.