Line an 8x8 baking dish with parchment paper (leave the edges hanging off the sides so you can lift the fudge out the dish) and set aside.
Add together the sugar, butter and heavy cream into a large sauce pan, bring to a boil over medium heat.
Reduce the heat to medium low, cook for 7 minutes, stir constantly. You can check to see if it’s ready but dropping a drop of it in a glass full of iced water, if you can grab the ball and it’s fudge like, then it’s perfect.
These next few steps need to be done pretty fast, remove from heat and immediately put in the white chocolate chips, stir until it’s melted and mixed well. Add the marshmallow creme and mix well to combine.
Add the vanilla pudding and vanilla extract and mix until combined and smooth. Pour 2/3 of the fudge into the parchment paper lined pan.
Immediately whisk the cocoa powder into the remaining fudge in the pan, mix until combined. Pour the chocolate mixture on top of the custard fudge in the pan. Use a knife and make swirls around the fudge.
Let cool to room temp and then cut into 16 cubes. In a microwave safe bowl add the semi sweet chocolate chips and vegetable oil, microwave for 30 seconds at a time stirring each time until melted and smooth.
Let the chocolate cook for 15 minutes, once cooled down, pick up the fudge and dip the tops into the chocolate. Place the fudge on parchment paper and let the chocolate set and harden for about an hour. Serve and enjoy!