Heat oil in a heavy pan and brown the brisket on both sides, if desired. Add liquid and seasonings and bring to a simmer. Cover and simmer until the brisket is fork-tender, 2 to 3 hours. This preparation is also called “boiled beef.”
To braise corned beef, trim off any excess fat, place the corned beef in a heavy pot, and add cold water. Simmer until the meat is firm but tender, 2 to 3 hours.
Rub the brisket with salt and spices, place it in a roasting pan, cover, and bake at 325°F (163°C) until fork-tender, 3 to 4 hours.
Cover the brisket with liquid and seasonings and cook 6 to 8 minutes on High, then continue to cook on Medium for a total of 50 to 55 minutes or until the meat is fork-tender.