4 lb. chicken
4 Tbs. olive oil
3 large potatoes (about 2 lbs.), peeled, quartered lengthwise, then halved crosswise
4 large carrots, peeled, quartered lengthwise, halved crosswise
6 celery stalks, cut into 3-inch pieces
1 1/2 tsp. dried oregano
3/4 tsp. garlic powder
Preheat oven to 425 degrees. Rinse chicken; pat dry with paper towels. Rub chicken with 1 Tbs. oil; sprinkle with salt and pepper. Place in center of large roasting pan. Roast 15 minutes.
Meanwhile, toss potatoes, carrots and celery with remaining olive oil in large bowl to coat. Crumble oregano in small bowl; mix in garlic powder. Sprinkle all but 1/4 tsp. oregano mixture over vegetables; toss to coat.
Arrange vegetables around chicken in roasting pan. Sprinkle chicken with remaining oregano mixture. Roast chicken and vegetables until cooked through and golden, brushing chicken once with any pan juices and turning vegetables over once with spatula, about 1 hour. Arrange chicken and vegetables on platter. Scrape any pan juices into bowl and serve alongside meat.