Line a 9x13-inch baking dish with parchment paper.
In a large saucepan, over medium heat, mix sugar, butter, and evaporated milk.
Bring mixture to a boil and leave on heat until the mixture registers 234°F on a candy thermometer (about 5 minutes), stirring constantly.
Remove from heat and stir in white chocolate chips until melted and thoroughly combined.
Beat in marshmallow fluff. Then, reserve 1 cup of the mixture and set aside.
Add in the orange extract and food coloring and pour into the prepared pan.
Working quickly, dollop the reserved mixture over the top and swirl with the back of a knife.
Allow fudge to cool and set for about 2 hours before cutting.