Preheat the oven to 450 degrees F (232 degrees C). Place an oven safe rack over a baking sheet.

If possible, let the chicken rest at room temperature for 30 minutes before roasting. (This will ensure more even cooking.)

Place the chicken onto a cutting board, breast side down. Use kitchen shears to cut away the spine. (You can discard it or use it to make gravy.)

Use your hands to open up the chicken like a book, then flip it over, open side down. Use the heel of your hand to push down on the chicken breast, which will crush the breast bone and allow the chicken to lay flat.

Transfer the butterflied chicken to the rack over the baking sheet, breast side up.

To make compound butter, mash together butter, parsley, Italian seasoning, and crushed garlic.

Run your hands under the chicken skin on the breast and legs to separate it from the chicken underneath. Place dollops of compound butter all over underneath the skin and then press down over the skin to spread around underneath.

Drizzle olive oil over the chicken, over the skin. Sprinkle with sea salt, paprika, and black pepper.

Roast spatchcock chicken in the oven for 40-50 minutes, until a thermometer in the thickest part of the breast reaches 160 degrees F (71 degrees C). (Temperature will rise about 5 degrees while resting.)

Remove chicken from the oven and let it rest for 10-15 minutes before cutting into it.