In a large microwave-safe bowl, combine the white chocolate chips, sweetened condensed milk, and a pinch of salt. Microwave for 30 seconds.

Stir well, then continue microwaving in 30-second increments, stirring each time, until the chocolate is melted and fully combined with the milk.

Line a square baking dish with parchment paper. Pour in the fudge mixture and smooth it out evenly.

Sprinkle with Christmas sprinkles and chill in the refrigerator for at least 4 hours before cutting into squares.