Prepare a nine-by-13-inch baking dish by greasing it with butter. (This will give you about two-inch tall pieces. Use two dishes if you want something thinner.) Set it aside.

In a large, heat-proof mixing bowl, add the chopped Hershey bars, chocolate chips, marshmallow crème and margarine, and set it aside, as well.

In a medium-sized saucepan, add the sugar and evaporated milk, and heat it over medium-low heat, stirring regularly, until it reaches soft ball stage (240 degrees). (Be careful to watch it, because it can overflow easily.)

Pour the hot sugar mixture over the ingredients in the mixing bowl and beat until everything is well combined. Beat in the vanilla, and fold in the chopped walnuts.

Spread the mixture out evenly in your prepared pan(s), and press a whole walnut into each spot where you’ll want to cut a piece of fudge.

Let the fudge cool completely on the counter or in the refrigerator, and then slice into one-inch pieces.

Store in an airtight container.