01 - Preheat the oven to 350°F (180°C) with fan or gas mark 4.
02 - In a small bowl, mix softened butter with parsley, thyme, rosemary, lemon zest, and minced garlic until fully combined.
03 - Pat the turkey crown dry, carefully loosen the skin, spread half of the herb butter beneath the skin, then rub the remaining butter evenly over the surface.
04 - Brush the turkey with olive oil, then season thoroughly with sea salt and freshly ground black pepper.
05 - Place lemon halves, onion, carrots, and celery in a large roasting pan, then set the turkey breast-side up on top.
06 - Pour chicken stock into the base of the roasting tray to maintain moisture during cooking.
07 - Roast for 1 hour and 45 minutes, basting every 30 minutes with pan juices; cover loosely with foil if the skin browns too fast.
08 - Verify that the thickest part of the breast reaches 165°F (74°C) to ensure proper cooking.
09 - Allow the turkey crown to rest covered loosely with foil for 20 minutes before carving.