15-Minute Old-Fashioned Hot Fudge Recipe

Gather the ingredients.

In a medium bowl, whisk together the sugar, flour, and cocoa powder.

In a medium saucepan over medium heat, combine the milk, butter, and vanilla. Cook, stirring, until the butter has melted.

Add sugar mixture to the milk mixture while constantly whisking.

Bring to a boil, stirring constantly until thick and smooth, about 5 minutes.

Remove the pan from the heat, transfer the sauce to a bowl, and let it cool completely.

Use right away or cover and refrigerate (once refrigerated, it will last for a week).