01 - Preheat oven to 300°F. Pat duck dry with paper towels and prick skin all over carefully without piercing meat.
02 - Season interior and exterior with salt and pepper. Stuff cavity with orange quarters, lemon quarters, thyme, rosemary, and smashed garlic.
03 - Place duck breast-side up on a rack in a roasting pan. Roast for 2 hours, basting occasionally with pan juices and draining excess fat as needed.
04 - In a small saucepan, combine orange juice, orange zest, honey, balsamic vinegar, and soy sauce. Bring to a boil then simmer for 12–15 minutes until reduced by half and syrupy. Whisk in butter and set aside.
05 - Increase oven temperature to 425°F. Brush duck generously with orange glaze and continue roasting for 20–30 minutes, basting once or twice, until skin is deep golden and crisp.
06 - Remove duck from oven and let rest 15 minutes before carving. Serve with remaining glaze.