Line 8-inch square pan with foil or parchment paper.
Over low heat, melt milk and semi-sweet chocolate chips, condensed milk, and salt; stirring constantly until smooth. Remove from heat and stir in 2 tablespoons peppermint chips. Spread into prepared pan.
Melt white chocolate squares in microwave safe bowl on HIGH for 20-30 seconds. Drizzle over fudge in pan. Sprinkle remaining 1/4 cup peppermint chips over fudge and press down slightly. Chill 2 hours or until firm. Cut into squares.