Prepare the Pan:
Line an 8×8 baking dish with foil, making sure the edges are overhanging for easy removal. Set aside.
Make the Caramel Layer:
In a medium saucepan over low to medium heat, melt the white chocolate chips and butter.
Stir in the Dulce de Leche until the mixture is creamy.
Add the marshmallow cream and stir until smooth.
Pour the caramel mixture into the prepared pan and refrigerate for 30 minutes or until slightly set.
Make the Coffee Layer:
Dissolve the instant coffee in the hot water and stir it into the sweetened condensed milk. Set aside.
In a clean saucepan over low to medium heat, melt the white chocolate chips and butter.
Stir in the coffee-infused sweetened condensed milk until creamy.
Add the marshmallow cream and stir until smooth.
Pour the coffee layer over the caramel layer and refrigerate for at least 4 hours or overnight until completely set.
Cut the Fudge:
Once set, lift the foil from the pan and peel it off the fudge.
Use a hot knife to cut the fudge into 36 small squares and allow them to come to room temperature.
Add the Dark Chocolate Drizzle:
Melt the dark chocolate wafers in the microwave for 30 seconds, stirring until smooth. Heat for another 15 seconds if needed.
Spoon the melted chocolate into a small ziplock bag and snip off one corner. Drizzle the chocolate over the fudge squares.
Let the chocolate set before serving or storing.
Serving:
Store the fudge in an airtight container at room temperature.