Place corned beef and seasoning from package in a large pot. Cover with water. Bring to a boil. Simmer over low heat until tender, about 2 1/2 hours.
Test for doneness with a fork. Preheat oven to 350 degrees. In a mixing bowl, combine the marmalade, mustard, brown sugar and garlic.
Remove meat from pot and drain. Place on a oven-proof dish or pan. Spread glaze over meat to cover.
Bake at 350 degrees for 30 to 35 minutes or until glaze is just brown and crisp. Slice meat & serve either hot or cold. It is also great when served with steamed cabbage, boiled new potatoes and Farm To Market Rye Bread.
Jaspers Notes: "Corned Beef and Cabbage" was a traditional dish served for Easter Sunday dinner in rural Ireland. The beef, because there was no refrigeration at that time, was salted or brined during the winter to preserve it, It was then eaten after the long, meatless Lenten fast. It is traditionally served on St. Patricks Day throughout the United States.