Empty Pasta mix into 3-quart saucepan 2/3 full of boiling water. Gently boil uncovered 12 minutes, stirring occasionally.
Drain pasta; rinse with cold water. Shake to drain well. In medium bowl, stir together seasoning mix and dressing. Add pasta; toss to combine.
In 3- or 4-quart glass salad bowl or 13x9-inch glass baking dish, layer lettuce, carrots, broccoli and pasta mixture. Top with tomatoes. Serve immediately, or refrigerate.