Place meat in large saucepan; top with onions, garlic and bay leaves.
Add enough water to cover all ingredients; cover with lid. Bring to boil; simmer on medium-low heat 1 hour.
Drain, reserving meat in pan.
Remove and discard bay leaves.
Add enough fresh water to saucepan to cover meat; cover with lid. Bring to boil; simmer on medium-low heat 2 to 3 hours or until meat is tender.
Heat oven to 350F.
Remove meat from pan, reserving liquid in pan; place meat in shallow baking pan.
Mix syrup, mustard and horseradish; spoon half over meat. Reserve remaining syrup mixture for brushing onto cooked meat.
Bake 20 min., brushing frequently with remaining syrup mixture. Meanwhile, add cabbage to reserved liquid in saucepan; cook 8 to 10 min. or until tender.
Place meat on platter; drizzle with pan drippings.