Source

https://foodwishes.blogspot.com/2009/11/oh-fudge-carnations-classic-chocolate.html

Ingredients:
2 tablespoons butter or margarine
2/3 cup evaporated milk
1-1/2 cups granulated sugar
1/4 teaspoon salt
1 teaspoon vanilla extract
2 cups (4 ounces) miniature marshmallows
1 1/2 cups (9 ounces) semisweet chocolate chips
1/2 cup chopped pecans or walnuts, optional

Instructions

Add butter, evaporated milk, sugar, salt to heavy pan on medium heat until simmering.
Simmer for five minutes
Turn heat OFF
Add vanilla extract.
Add chocolate
Add marshmallows
Stir until smooth
Pour into 9x9 pan lined w/ plastic wrap (or foil?)
let cool until room temp
wrap/cover w/ plastic wrap and chill overnight or until hard.