Harry Potter's "Butterbeer" Recipe

In a small saucepan, combine the brown sugar and water over medium heat. You want to bring this to a gentle boil and cook it until the mixture reads 240 degrees Fahrenheit on a candy thermometer. Don't forget to stir often so it doesn't burn.

Mix in the butter, salt, vinegar and 1/4 heavy cream. Set this aside to cool to room temp. Once this has cooled, you can mix in the rum extract.

In a medium sized bowl, you will need to mix 2 tablespoons of brown sugar mix and the rest of the heavy cream. Use an electric mixer to beat until it just starts to thicken up but not completely whipped.

Split the brown sugar mixture into 4 different tall glasses (1/4 cup for every glass). Then you want to add about 1/4 cup of cream soda to every glass, then stir to combine. Fill each glass nearly to the top with additional cream soda, then spoon the whipped topping over each.