Corned Beef Briskets. There are a few 5-6 lb roasts, but most are in the 3 lb range. I choose a piece that allows 1 lb per serving, to account for shrinkage, fat loss, and maybe some left-overs. You can cook your corned beef many ways: oven, slow cooker, maybe even your instant pot. I usually prepare corned beef as part of a boiled dinner, using my old cast iron Dutch Oven. Rinse the brisket under cold water very briefly to removed excess salt. Place it in the Dutch oven with a couple of crushed garlic cloves, celery and onion. Add enough water to cover. Bring to a boil, skimming scum from surface. Cover pot, reduce heat, and let simmer for 2 hours. I put it in the oven at 250 degrees. Uncover the pan, adding potatoes, carrots, parsnips, turnips and cabbage. Cover, and continue to cook until the meat and vegetables are tender, about 11/2 hours more. Serve it with a nice grainy mustard and/or horseradish sauce. Sometimes I’ll make a pour-over from the water in the pot, but I’ll taste that first and make sure it isn’t too salty.
Sometimes I just put a rinsed corned beef brisket into a covered roaster and put it in the oven at about 225 degrees for 6-7 hours, until it is fork tender and registers about 165 degrees.