Add sliced onions to the dutch oven and saute until just tender. Then add white wine wine and garlic, stirring to deglaze the pan.
Next return the roast to the pan. Add enough milk to raise the liquid level to half way up the roast. Cover the dutch oven and start the braising process on the stove top, bringing the liquid to a gentle boil, then transfer to the oven.
Plan on 2 1/2 - 3 hours of total cooking time. We started at 300 degrees. About 30 minutes in, we went down to 275 degrees, then 30 minutes later settled at 250 degrees for the duration of the cooking time. When the meat separates easily with a fork, remove it and allow to rest 15 minutes before slicing.