Line an 8x8 inch baking pan with parchment paper, leaving some overhang on the sides.

In a medium saucepan, combine the sugar, heavy cream, butter, and salt. Cook over medium heat, stirring constantly, until the sugar is dissolved and the mixture comes to a boil.

Clip a candy thermometer to the side of the pan and continue to cook, without stirring, until the thermometer reaches 235°F (113°C), the soft-ball stage.

Remove from heat and stir in the peppermint extract and marshmallow creme until smooth.

Quickly stir in 0.25 cup of the crushed candy canes. Pour the fudge into the prepared pan and spread evenly.

Sprinkle the remaining 0.25 cup of crushed candy canes over the top, gently pressing them into the fudge.

Let the fudge cool completely at room temperature for at least 2 hours, or until firm. For faster results, you can chill it in the refrigerator.

Once the fudge is firm, use the parchment paper overhang to lift it out of the pan. Cut into squares and serve.

Store in an airtight container at room temperature.