LINE 8-inch-square baking pan with foil.
COMBINE sugar, evaporated milk, butter and salt in medium, heavy-duty saucepan. Bring to a full rolling boil over medium heat, stirring constantly. Boil, stirring constantly, for 4 to 5 minutes. Remove from heat.
STIR in marshmallows, morsels, 1/2 cup nuts and vanilla extract. Stir vigorously for 1 minute or until marshmallows are melted. Pour into prepared baking pan. Sprinkle remaining 2 tablespoons of nuts over top of fudge; carefully press nuts into the fudge. Refrigerate for 2 hours or until firm. Lift from pan; remove foil. Cut into 48 pieces.