01 -
Line 8x8 pan with foil and butter it. Don't use larger pan or fudge will be too thin.
02 -
Mix milk, sugar, and salt in heavy pan or double boiler. Boil 5-6 minutes, stirring constantly.
03 -
Remove from heat. Stir in marshmallows, chocolate, zest, and juice until smooth.
04 -
Pour into pan, spread evenly. Cool completely.
05 -
Slice into 1-inch squares.