Cooking Steps
Preheat the oven to 300 degrees F (150 degrees C).
Place corned beef brisket in the center of a roasting pan.
Arrange potatoes and carrots around the sides, then scatter onion and garlic over top.
Sprinkle seasoning packet over beef, then pour in water until potatoes are almost covered.
Cover the roasting pan with a lid or heavy-duty aluminum foil.
Roast in the preheated oven until corned beef is so tender it can be flaked apart with a fork, about 5 to 6 hours.
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