Remove the brisket from the packaging and rinse under cold water to remove excess brine.
Place the corned beef in a large pot or Dutch oven. Add water until the meat is covered. Add the spice packet, garlic, bay leaves, and peppercorns.Bring to a boil, then reduce heat to low. Cover and simmer gently for 2½–3 hours, until the meat is tender.
About 30 minutes before the meat is done, add the potatoes, carrots, and onion.
Place cabbage wedges into the pot during the last 10–15 minutes of cooking so they soften but don’t overcook.
Remove the brisket from the pot and let it rest for 10 minutes. Slice against the grain for maximum tenderness. Serve with the vegetables and some broth.