Stud the rinsed and peeled rack of corned beef ribs with the three cloves, fairly evenly spaced along the top meaty side of the ribs.
Place the ribs in a large, deep covered roasting pan or Dutch oven.
Sprinkle the peppercorns on top of the ribs along with the slices of garlic and the bay leaves.
Add enough water to just cover the ribs - this will vary depending on the size of your pan.
Put the pan, covered, into the oven and cook for one hour.
While the ribs are braising for the first hour, prepare the vegetables.
After the first hour, add all the vegetables, except for the cabbage, into the pan. Re-cover and return to the oven for 45 minutes.
After the 45 minutes, add the cabbage to the pan, re-cover and return to the oven for fifteen minutes.
During the final braising of the ribs and vegetables, prepare the glaze.
Combine the sugar, beer and vinegar in a small saucepan and heat to a boil over medium heat.
Cook at a low boil for 5 minutes, stirring often.
Remove the glaze from the heat, add the mustard and stir to combine.
Set aside until ribs and vegetables are finished braising.
Remove the vegetables and ribs from the oven when the cooking time is complete (about 2 hours).
Remove the ribs and place on a baking rack set over a pan. Re-cover the vegetables to keep them warm while you glaze the ribs.
Brush a light coat of glaze on the underside of the ribs and a thicker layer on the top side. Use about 1/2 the glaze.
Place the ribs into the oven and cook for 15 minutes. This will give you a good base layer of glaze.
After 15 minutes, remove the ribs for a final coating and turn the oven up to 425°
Brush the rest of the glaze on the ribs, return to the oven and cook for 10 to 15 minutes more, until the glaze is lightly browned and bubbly but not burned.
When the glazed ribs are done, allow to cook for a couple of minutes (that sugar will be hot!).
Remove the vegetables from the braising liquid and serve with the ribs on a platter to serve and cut at the table or cut the meat into rib sections. If you wish to forego the vegetables, by the way, the ribs make a fantastic appetizer all on their own.