Corned Beef and Cabbage with Horseradish Sauce

I love corned beef.  I love horseradish.  The two together should be a little slice of heaven...OK how about a big hunk of heaven with some yummy sauce on top.  I may practice this once or twice with St. Paddy's Day approaching
1-3lb. corned beef brisket
16 C. cold water
2 bay leaves
2 tsp. black peppercorns
4 whole allspice berries
2 whole cloves garlic
3 carrots, peeled and cut into large wedges
2 onions, peeled and quartered
1/2 large head cabbage, cut into 8 thick wedges
8 small new potatoes, halved
Freshly ground black pepper

For the horseradish sauce
3/4 C. mayonnaise
3/4 C. sour cream
1/4 C. plus 2 tbsp. jarred horseradish
1/2 tsp. lemon zest
Salt and pepper to taste

Preheat the oven to 275 degrees.

Place the corned beef in a colander set in the sink and rinse well under cold running water.

Place the beef in a large covered roaster.  Add the water, bay leaves, peppercorns, allspice, cloves, carrots, and onions.  Bring to a boil, reduce to a simmer, and skim any scum that rises to the top.  Cover and transfer pan to the oven and braise until very tender, about 4 hours.

While the corned beef is braising, prepare the horseradish sauce.  In a small bowl, mix together the mayonnaise, sour cream, horseradish and zest.  Season with salt and pepper to taste. Refrigerate the sauce for at least 30 minutes before serving.

Transfer the corned beef to a cutting board and cover tightly with foil to keep warm.

Add the cabbage and potatoes to the cooking liquid and bring to a boil.  Lower the heat and simmer until the vegetables are tender, about 20 minutes.

Using a slotted spoon, transfer the cabbage to a large platter.  Slice the corned beef across the grain of the meat into thin slices.  Lay the slices over the cabbage and surround it with the potatoes, carrots and onions.

Ladle some of the hot cooking liquid over the corned beef and serve with horseradish sauce.