Line a 13x9x2-inch baking pan with parchment paper; set aside.
In a large saucepan, combine the sugar and gelatin. Stir cream and salt. Add butter. Cook and stir over medium heat until the butter melts and sugar is dissolved. (The mixture will just begin to simmer.) Remove from the heat. Add the chocolate, marshmallow creme, orange extract, vanilla bean paste, and nutmeg. Stir until no fluffs of creme remain. Pour into prepared pan.
Cover loosely and chill overnight. When fudge is firm, use parchment to lift it out of pan. Cut into diamond-shaped pieces. Top each with a red candy, if desired. Store, tightly covered, in the refrigerator for up to 3 weeks.