In a microwave-safe bowl, combine white chocolate chips and butter. Microwave in 20-second intervals, stirring until smooth.

In a separate mixing bowl, beat cream cheese until smooth. Gradually mix in sweetened condensed milk until fully incorporated.

Stir the melted chocolate blend into the cream cheese mixture, then add vanilla extract. Gradually add powdered sugar until thick yet pourable.

Prepare a baking dish by lining it with parchment paper and sprinkle graham cracker crumbs evenly over the bottom.

Pour the fudge mixture over the graham cracker layer and spread evenly. Tap the pan to release any air bubbles.

Refrigerate for at least 3 hours, ideally overnight, to let the fudge firm up.

Lift the fudge out using the parchment overhang and cut into squares for serving.