Line an 8x8 baking dish with parchment paper. Be sure to leave a bit of an overhang to help lift the fudge out of the baking dish. (If you do not have any parchment paper on hand, you can use heavy-duty aluminum foil. Lightly spray with nonstick cooking spray to keep the fudge from sticking to the foil.)

Add the white chocolate chips, sweetened condensed milk, and 2.5 tablespoons heavy cream to a medium-sized microwave-safe bowl. Heat in 30-second intervals, stirring well after each interval until the chips are melted and smooth.

Add the unwrapped caramels and 1.5 tablespoon of heavy cream to a small microwave-safe bowl. Heat in 30-second intervals, stirring well between each interval until the caramels are melted and smooth.

Fold ¾ of the caramel mixture into the white chocolate mixture. Fold the mixture 3-4 times, being careful not to blend the caramel into the white chocolate; you only want a marble effect.

Evenly spread the white chocolate mixture into the prepared baking dish. Dollop the remaining caramel in several spots on top of the fudge. Use a knife to swirl the remaining caramel on top of the fudge. Cover the baking dish with plastic wrap. Chill in the refrigerator for at least 4 hours or until the fudge is set.

Use the parchment paper to lift the fudge out of the baking dish. Use a sharp knife to carefully slice the fudge into 5 slices x 5 slices. Keep the fudge in the refrigerator until ready to serve.