Place potato in a large bowl. Combine rosemary and next 4 ingredients; stir well. Pour one-third of oil mixture over potato; toss well.
Place potato in one end of a large roasting pan coated with cooking spray. Bake at 450° for 8 minutes. Place red pepper in bowl; add half of remaining oil mixture. Toss well; place red pepper next to potato, and bake 5 minutes. Place eggplant and garlic in bowl; add remaining oil mixture, and toss well. Add to potato and red pepper, and bake 20 additional minutes or until vegetables are tender. Arrange vegetables on a serving platter. Serve immediately.