Step 1

Preheat oven to 325˚F.

Step 2

Submerge corned beef in cold water for 15 minutes. Drain and pat dry.

Step 3

Place corned beef in a baking dish and add Guinness to the pan.

Step 4

In a small bowl, stir together the brown sugar, mustard and seasoning packet that came with the corned beef. Rub this onto the top of the corned beef.

Step 5

Cover the pan and bake for 4 hours, removing the cover for the final 30 minutes of cooking.

Step 6

Remove from oven and allow the corned beef to rest for about 10 minutes before slicing.