For the Ham: Put water in a pot and cover, bring to a boil. Take the foam off the top. Let simmer for 4 hours. Let ham sit in broth over night, covered in refrigerator.
For the Mustard Mix: Preheat oven to 350 degrees. Whisk ingredients well and brush the mix on the ham. Bake the ham for 30 minutes or until the mustard crust is golden brown.
Recipe courtesy of Marcus Samuelsson, Aquavit, New York, NY