Pre-heat oven to 350°F In a medium saucepan, heat the oil and add the onions and garlic. Cook for one to two minutes. Add gravy, tomatoes, and italian seasoning.
Meanwhile, heat potatoes and gently fold in broccoli and carrots. To each slice of roast beef, spread about 1/2 cup of the potato mixture and roll up. Place beef rolls, seam side down, in a baking dish sprayed with non-stick cooking spray.
Spoon gravy mixture over beef rolls, cover and bake for 20-25 minutes. Uncover, sprinkle with parsley and parmesan, and serve.