Here is the recipe for the homemade fudge sauce:
1 cup heavy whipping cream
1 cup sugar
1/2 cup butter, cubbed
1 cup baking cocoa
In a large saucepan, combine cream, sugar and butter. Cook and stir until sugar is dissolved. Bring to a boil, without stirring. Reduce heat; simmer uncovered for 3 min. Cool for 3 min.
Place cocoa in a heat proof bowl. Whisk hot liquid into cocoa until smooth. WARNING: VERY RICH!