Preheat Oven: Set oven to 425°F (220°C) and lightly oil a large roasting pan.
Marinate: In a large bowl, toss the chicken and potatoes with lemon juice, olive oil, garlic, dried oregano, salt, rosemary, black pepper, and cayenne until well coated.
Assemble: Arrange chicken skin-side up in the roasting pan. Nestle potatoes around the chicken and drizzle with ⅔ cup of chicken broth. Pour any remaining marinade over the top.
Bake & Toss: Roast for 20 minutes, then toss the potatoes and turn the chicken skin-side up again.
Finish Cooking: Continue baking for about 25 more minutes, or until the chicken is golden brown and registers 165°F (74°C) on an instant-read thermometer. Transfer chicken to a serving platter and keep warm.
Broil the Potatoes: Toss the potatoes in the pan juices, then broil for about 3 minutes until crispy. Transfer to the platter with the chicken.
Make the Pan Sauce: Place the roasting pan on the stovetop over medium heat. Add the remaining ⅓ cup chicken broth and scrape up the browned bits. Strain the pan juices and drizzle over the chicken and potatoes.
Serve: Sprinkle with fresh oregano and enjoy!