Preheat oven to 425°F (218°C) and position a rack in the center.

Remove giblets and pat the chicken skin completely dry using paper towels to ensure optimal browning.

Season the internal cavity with salt and pepper, then insert one lemon half, one orange half, and the smashed garlic.

Combine softened butter with rosemary and thyme in a small bowl.

Gently loosen the skin over the breast and rub half the herb butter underneath; rub the remaining butter over the entire exterior of the bird.

Truss the legs with kitchen twine and tuck the wings under the body to prevent burning.

Place chicken in a roasting pan, drizzle with olive oil, and squeeze the juice from the remaining citrus halves over the skin.

Roast for 75 minutes, or until an instant-read thermometer inserted into the thickest part of the thigh (avoiding bone) registers 165°F (74°C).

Remove from oven and let rest on a carving board for 15 minutes to allow juices to redistribute before serving.