Line an 8x8 in square pan with parchment paper and spray the parchment with cooking spray.
In a medium saucepan heat 4 tablespoons butter, marshmallows, sugar, cocoa powder and heavy cream over medium to low heat stirring frequently until melted and smooth.
With the heat on low add in vanilla and white chocolate chips, mix until chips are smooth and melted.
Remove from the heat and add in food coloring, stir until well incorporated and add more to achieve desired color.
Pour the mixture into your prepared pan and place in the refrigerator for at least an hour.
To make the topping-
In a medium bowl cream together butter and cream cheese with an electric mixer. Add in powdered sugar and vanilla mixing until well incorporated.
In a microwave safe bowl heat 1/3 cup white chocolate chips in 30 second increments, stirring between each one, until completely melted.
Pour the melted chocolate into the butter and cream cheese mixture and mix on low to blend well.
Pour the mixture over the refrigerated red fudge layer and spread it evenly. Sprinkle with sprinkles if desired.
Refrigerate until cream cheese layer is chilled.
Remove from the pan and cut into 16 even squares.
Keep refrigerated in an airtight container.