Line an 8"x8" pan with two strips of parchment paper the width of the pan with at least 3" of overhang on each side.
In a glass bowl, mix chocolate, butter, milk and salt. Place bowl over double boiler with simmering water. Stir until chocolate is smooth, about 5 - 10 minutes. Or put in microwave for 1 minute at a time until melted and well blended, this is easier but must be watched carefully not to over cook.
Remove bowl from heat, and stir in extract,coffee, or coffee liqueur. Fold in nuts/dried fruit of choice. Pour mixture into prepared dish and smooth with spoon or offset spatula.
Chill in fridge until set, about 1 ½ hours. Cut fudge into desired size with a sharp knife.