Start by lining a 9x9-inch baking pan with parchment paper.
In a medium saucepan over medium heat, combine the butter, granulated sugar, and heavy whipping cream. Stir continuously until the mixture comes to a gentle boil.
Once boiling, remove the saucepan from heat. Stir in the cherry gelatin, white baking chips, and marshmallow creme. Mix until everything is melted and combined into a smooth mixture.
Add the cherry or vanilla extract, cocoa powder, and Coca-Cola to the mixture. Stir well to incorporate all the flavors.
Gradually add the powdered sugar and the vanilla extract. Mix until the fudge is thick and creamy.
Gently fold in the drained maraschino cherries, ensuring they are evenly distributed throughout the mixture.
Pour the fudge mixture into the prepared baking pan. Spread it evenly and tap the pan gently on the counter to remove any air bubbles.
Refrigerate the fudge for at least 4 hours or until it is completely set. Once firm, lift it out of the pan using the parchment paper and cut it into squares.
