Remove the chicken giblets and pat the chicken dry with paper towels.
Place the chicken on a large cutting board, breast side down. Using kitchen shears, cut along one side of the chicken spine, separating it from the ribs. Repeat on the other side of the spine. Flip the chicken over onto its back and firmly cut the cartilage and soft bone down the middle of the breasts so the two halves come apart.
In a small bowl, combine the butter, oil, lemon zest, thyme, garlic, paprika, salt and pepper. Rub the seasoned butter evenly over the chicken halves, getting some under the skin, then let them rest for 30 minutes at room temperature.
Preheat the oven to 425 degrees F. (220°C)
Transfer the chicken haves to a deep baking sheet, roasting pan, or oven-safe skillet, skin side up. Roast the chicken for 35 to 40 minutes, basting with the released juices every 10 to 15 minutes, until the internal temperature registers at 165F, or until the juices run clear when the chicken is cut. You can broil the chicken for 2-4 minutes at the end of the cook time to crisp up the skin if you'd like.
Remove the chicken from the oven. Cover loosely with foil and rest for 10-15 minutes before serving.
Notes
Storage: Store leftovers in a sealed container in the refrigerator for up to 3 days. Reheat in the oven, microwave or use in other dishes like salads or casseroles.