Low and slow for this fall-off-the-bone braised lamb shoulder with grapes. Carve and serve it or throw it back in the pan for those crispy edges!
Preheat the oven to 325 degrees F. Let the lamb should sit at room temperature for at least 30 mins before roasting.
Rub the salt, pepper and garlic powder all over the lamb, rubbing it into the meat.
Heat 1 Tbsp oil until hot but not smoking in a large oven-safe pan or roasting pan (I use an enamel coated dutch oven). Place the lamb, fat-side down into the pan and sear until browned on all sides.
Remove the lamb to a plate and pour off all but 1 Tbsp of drippings. If the drippings are burnt, pour off all of them, wipe out the pan and heat another Tbsp of oil until hot.
Add the onions and smashed garlic cloves, season with salt and pepper, and saute until golden, about 5 mins.
Deglaze with the white wine and reduce by half. Place the lamb back in the pot and add the stock, 2 cups of grapes, and the thyme sprigs. The liquid should come to about 1/3 of the lamb. Add more stock if needed.
Cover and roast for 3 hours, checking occasionally and adding more water or stock if the pot is becoming to dry.
When the lamb is fork tender, remove it to a plate or platter and tent with foil. Drain off the fat, strain the drippings, and discard the solids.
Return the strained sauce to the pan and bring to a boil. Add the remaining grapes to the sauce and cook until the sauce is slightly reduced. Remove the bone from the lamb, slice and serve with the sauce.