S'Mores Doughnuts

Ingredients

• For the Doughnuts:
• 3
  cups all-purpose flour
• ¼
  cup sugar
• ½
  teaspoon kosher salt
• ¼
  cup warm water, about 100 F
• 2 ¼
  teaspoons active dry yeast (1 (0.25-ounce) packet)
• ¾
  cup milk, lukewarm
• 1
  large egg
• 3
  tablespoons melted butter
• 1
  teaspoon vanilla extract
• 1
  (13- to 16-ounce) container Marshmallow Fluff or creme
• Vegetable oil, for frying
• For the Chocolate Glaze:
• ¼
  cup butter
• 2
  tablespoons milk, half-and-half, or light cream
• 1
  tablespoon light corn syrup
• 1
  teaspoon vanilla extract
• 2
  ounces bittersweet chocolate, cut into small pieces
• 1
  cup confectioners' sugar
• ½
  cup graham cracker crumbs