Preheat the oven to 400 degrees F.

Line a large roasting pan with foil and then add parchment paper.

Layer the onions and whole garlic cloves and rosemary at the bottom of the pan.

In a small bowl, mix the balsamic vinegar with the citrus juice, olive oil and spices.

Use a small knife and poke the meat lightly, just enough to insert a bit of the garlic clove inside.

Take the cut up garlic cloves and fresh rosemary leaves and insert it among the slits you made in the meat.

Place the American lamb shoulder on the roasting pan and drizzle with the balsamic sauce.

Massage the sauce on the back and front of the meat, and rub it in well.

Make sure the meat is placed on the roasting pan over the onion slices with the fat side up. 

Pour the stock around the shoulder. 

Place a layer of parchment paper and then foil to secure the pan is tightly sealed.

Roast the lamb for 1 hour and drop the temperature to 350 degrees F. Let the meat roast for another 2-2.5 hours until tender. Flip the pan halfway for even heating and roasting.

Keep the lamb covered for 10-15 minutes to rest slightly and cool down a bit before serving.

Make the fresh pomegranates glaze by mixing all ingredients together in a bowl.

Remove the lamb and serve on a platter drizzled generously with the pomegranates. 

Enjoy