Line an 8x8-inch or 9x9-inch square baking dish with parchment paper, leaving an overhang for easy removal.
In a medium saucepan over low heat, combine the white chocolate chips and sweetened condensed milk. Stir constantly until the chocolate is fully melted and the mixture is smooth.
Remove from heat. Stir in the vanilla extract and salt, then fold in the dried cranberries. Reserve a few for topping if desired.
Pour the mixture into the prepared pan, smoothing the top. Sprinkle with additional cranberries or nuts if using. Refrigerate for at least 2 hours, or until fully set. Once firm, lift from the pan and cut into small squares.
