Line a 9x13 pan with parchment paper. Set it aside.
Add the sugar, butter, and evaporated milk to a large heavy duty sauce pot over medium heat. 2.5 cups granulated sugar, 1/2 cup butter, 5 oz evaporated milk
Stir the mixture occasionally as it comes to boil. Once the mixture is at a full rolling boil, stir it constantly until the fudge reaches 234 F (this will take 4 to 5 minutes)
Remove the pot from the heat and add in the white chocolate. Stir until its totally melted and combined. 2 cups white baking chips
Add in the marshmallow fluff, vanilla extract, and salt and stir until combined. 7 oz marshmallow fluff , 1 tsp vanilla extract, 1/4 tsp salt
Separate out 2 cups of the fudge mixture into another bowl.
Add the orange extract, and orange food coloring and stir until it reaches your desired color and flavor. 2.5 tsp orange extract, orange food coloring
Restir the vanilla fudge until smooth.
Add one spoonful at a time, alternating between the vanilla fudge, and the orange fudge into the prepared pan until its all been added.
Use a knife, or toothpick, gently marble the fudge to create a swirled pattern on the top.
Cover the fudge and let it sit until the fudge is set for at least 3 to 4 hours, or place it in the fridge to chill faster.
Slice it up and serve.