Preheat you oven to 425 degrees. (Optional) If cooking your chicken with potatoes and veggies, spread them across the baking sheet. Toss them in a tablespoon or two of olive oil and season with salt and pepper.
In a small bowl, combine the softened butter, diced rosemary, minced garlic, paprika, salt, pepper, lemon zest, lemon juice, and olive oil. Stir to combine and set aside.
Place your spatchcocked chicken onto the center of the baking sheet. Pat dry with a paper towel. Rub the butter mixture generously all over the chicken. Gently loosen the skin around the neck and place some of the butter between the skin and the meat. Use all of the butter.
Slice up the unused half of your lemon and place the extra lemon slices and a few extra rosemary sprigs onto the baking sheet as well. Place into your preheated oven.
Cook for about 45 minutes or until the chicken registers an internal temperature between 160 and 165 degrees. You’ll want to measure for the temperature in the thigh, making sure to avoid bones (to get an accurate temp). If your chicken starts to brown too much while baking, loosely cover with foil or lower the oven temperature to 400 degrees for the remainder of the cooking time.
When the chicken is done, remove from oven and let sit for 5-10 minutes before removing to a cutting board. Slice up the chicken and serve it with the roasted potatoes and veggies. Enjoy!