juice and finely chopped zest of 2 large limes, divided
¼ teaspoon salt
2 tablespoons white rum (or 2 teaspoons rum extract)
12 ounces chopped white chocolate bars or white chocolate chips (minimum 20% cocoa butter)
1 tablespoon finely chopped fresh mint leaves
Directions
Grease an 8-inch square baking pan and line with parchment paper to create an overhang on two sides.
In a heavy, large saucepan, combine the marshmallow creme, sugar, evaporated milk, lime juice, and salt. Bring mixture to a rolling boil over medium heat, stirring constantly to prevent scorching.
Reduce heat to medium-low and cook for an additional 5 minutes, stirring the entire time.
Remove the pan from heat and carefully stir in the rum or extract (the mixture will bubble). If using rum, return the pan to medium heat and cook for 1 minute to allow the alcohol to evaporate.
Turn off the heat and stir in the white chocolate until melted and smooth. Fold in the lime zest and mint.
Pour the mixture into the prepared pan. Refrigerate fudge until firm, about 2 hours.
Once the fudge is firm, use parchment overhang as handles and carefully lift fudge out and place it on a cutting board. Cut into 36 squares using a long, sharp knife, then serve.