Hershey's cocoa fudge is made using 2/3 cup cocoa, milk, sugar and vanilla extract combined with butter and salt. In a 4-quart saucepan, cook all the ingredients, bringing the mixture to a boil until it reaches the soft ball candy stage. Spread the mixture in a pan and cool.
To prevent the fudge from sticking to the pan, line it with aluminum foil, use enough foil so the edges extend over the pan, and grease the foil with butter. Use a candy thermometer to test the heat of the fudge mixture and ensure it reaches a soft ball temperature of 234 degrees Fahrenheit. Alternatively, test the mixture's soft ball stage by dropping a small amount into a bowl of extremely cold water, if the mixture flattens when removed from the water, it is done. Avoid stirring the fudge mixture once it is removed from heat, and allow it to cool to room temperature before using a wooden spoon to beat it until it thickens. For best results, follow the recipe exactly, and avoid doubling ingredients.
To make fudge with nuts, stir 1 cup of almonds, or walnuts, into the mixture. Or, in addition to the nuts, add in one cup marshmallow creme, and increase the cocoa to 3/4 cup.