Sorry for the late reply (St. Patty's is over obviously) but my recipe is as follows:
Thefatguy's Corned Beef Heaven
Slice an entire brown onion into thick slices and line the bottom of a roasting pan. Add 2 Bay leaves and 2 cloves garlic. Lay the corned beef brisket (fat side up) on the bed of onions. Pour the liquid in the brisket bag over the works. Pour in one full bottle of Guinness stout. Sprinkle pickling spice from brisket bag over brisket.* Cover with foil and let it marinate in the fridge for 24 hours.
Remove from fridge and add carrots, potatoes and/or cabbage at this time, if desired. Recover with foil. Bake at 350 for 1 hour 15 minutes per pound. Finally, remove foil cover and turn oven to 375 for another 15 minutes to brown the top. Remove from oven and let rest for at least ten minutes. Cut with the grain and serve.
We eat this dish about once a month or more. I've done it in a Crock Pot too but it doesn't come out as good.
*(The pickling spice that comes with the brisket is usually of a low quality so I always buy high grade pickling spice at the store and add a little more. It may be hard to find and is pricey but one jar will last for many corned beefs and also goes great on other meats).