Submerge corned beef, fat side up, in water in a large pot. Cover and simmer over low heat until beef is tender when pierced with a fork (3 to 3 1/2 hours). You can chill overnight after boiling, just bring the meat to a simmer again the next day and continue with recipe)

Preheat oven to 450 degrees; line a baking sheet with foil, top with a rack and coat with non stick spray. (I used a broiling pan) Transfer beefto prepared rack, fat side up. Use a knife to trim off the fat.

Whisk all remaining ingredients together in a saucepan and bring to a boil over high heat until thickened, 3-4 minutes. Spoon glaze on to beef, roast for 10 minutes or until glaze is dark and sticky. Remove from oven and let rest for 15 minutes.

Transfer to cutting board and cut against the grain.