Step 1
Remove the lamb shoulder from the refrigerator 45–60 minutes before cooking.
Pat the meat completely dry using paper towels.
Trim only excess fat while leaving a thin protective fat layer.
Step 2
Mix olive oil, crushed garlic, salt, black pepper, thyme, and oregano in a bowl.
Massage the seasoning mixture thoroughly over every side of the lamb, including around the bone.
Step 3
Lightly wet three sheets of baking paper.
Wrap the lamb tightly with the baking paper.
Cover completely with two or three layers of heavy-duty aluminum foil, sealing every edge.
Step 4
Preheat the oven to 220°C (425°F).
Place a roasting pan filled with hot water on the bottom rack.
Position the wrapped lamb on a wire rack above the water tray.
Step 5
Roast at 220°C (425°F) for 2½ hours.
Reduce the temperature to 120°C (250°F).
Continue roasting for another 1½–2 hours until the meat becomes extremely tender.
Step 6
Carefully unwrap the lamb.
The meat should easily separate from the bone.
If using a thermometer, the internal temperature should reach approximately 93–96°C (200–205°F).
Step 7 (Optional)
Transfer the lamb to a roasting tray.
Brush with some cooking juices.
Roast uncovered at 230°C (445°F) for 8–10 minutes until lightly browned.
Step 8
Rest the lamb for 15 minutes.
Pull the meat apart using forks or tongs.
Serve immediately with the reserved roasting juices.