Step 1

Line a 9-inch square baking dish with aluminum foil and spray with cooking spray.

Step 2

In a medium saucepan, heat the sweetened condensed milk over medium heat, stirring frequently to prevent scorching, until hot. Add the white chocolate chips and stir until melted, 2 to 3 minutes. Stir in the cookie mix, butter, and salt until smooth; remove the mixture from the heat. Fold in the cookies, ¼ cup plus 2 tablespoons of sprinkles, and vanilla.

Step 3

Pour the fudge mixture into the prepared pan, smoothing the top. Top with the remaining 2 tablespoons of sprinkles and allow it to set up completely in the refrigerator before slicing, at least 2 hours.