In a small jar, combine the olive oil, the zest of 1 lemon, the juice from 2 lemons (about 1/4 cup), rosemary, garlic, smoked paprika, salt, and pepper. Whisk everything together until well mixed.
Arrange the chicken, skin-side up, in a 9x13 baking dish, then scatter the halved potatoes around. Pour the lemon mixture over both the chicken and potatoes, making sure to rub it in well to coat everything nicely.
Place 4 lemon halves into the dish alongside the chicken and potatoes.
Bake for 60 minutes until the chicken is completely cooked. For an extra crispy finish, broil for an additional 3-5 minutes until the chicken skin is beautifully golden brown.
For Serving:
Serve the dish with the chicken, potatoes, a lemon wedge, and a generous drizzle of the pan drippings over a bed of fresh arugula.