Preheat the oven to 350 degrees F. Set the chicken in a large roasting pan. Tie the legs together. Brush with 1 Tbsp. of the oil; season with salt and pepper then roast for 50 minutes. Meanwhile, boil the potatoes until tender on the outside, but still firm in the centre. Drain well and place in a bowl. Toss in the remaining oil, lemon zest and juice, garlic, paprika, oregano, salt and pepper.
After the chicken has roasted 50 minutes, baste with any pan juices and then surround with the potatoes. Roast 50 minutes more, or until the temperature in the centre of the thigh registers 170 degrees F on a meat thermometer. Transfer potatoes to a serving dish and keep warm in a 200 degrees F oven. Transfer the chicken to a plate, tent with foil, and rest 10 minutes before carving.
Note: If you desire gravy with the chicken, once the bird and potatoes are out of the pan, set it on the stovetop over medium-high heat. In a bowl, combine 2 1/2 cups chicken stock with 3 Tbsp. flour. Pour into the pan and simmer until a thickened gravy forms; season with salt and pepper.