Harry Potter's Homemade Butterbeer Recipe

Homemade Butterbeer 
Makes 6 servings
6 12-ounce bottles chilled cream soda, or 1/2 recipe Homemade Cream Soda, substitute diet cream soda for a still yummy sugar-free version
3 teaspoons (1 tablespoon) imitation butter flavor, or 2 tablespoons clarified butter (instructions linked above **clarified butter does not always blend well with the cold beverage, see info above**)
OPTIONAL – 1 ounce light rum, per serving, for adults only
FOR THE FOAM (Vegan/Dairy-free recipe linked here)
2 cups heavy cream
6 tablespoons sugar, or splenda for sugar free version
2 teaspoons vanilla extract
1 1/2 teaspoons imitation butter (if using clarified butter, double the amount to 3 teaspoons, or 1 tablespoon)
To make the butterbeer: Set out 6 16-ounce glasses. Place 1/2 teaspoon of imitation butter (or 1 teaspoon clarified butter) in each glass. Pour 12 ounces of cream soda into each glass, over the butter. Lightly stir, if necessary.
To make the foam: In a large bowl, or the bowl of a standing mixer, whip the heavy cream on medium high speed for 3-4 minutes until it starts to thicken. Add the sugar and continue whipping until very soft peaks begin to form, another 3-4 minutes (if you need to whip more or less, then be sure to do so, the times can vary quite a bit based on environment). Stir in the vanilla and imitation butter (or clarified butter), then whip for another 30 seconds or so, until soft peaks form.
Spoon a generous portion of foam on top of each glass of butterbeer, mixing gently, if desired (or spoon the foam into the bottom of the glass and pour the butterbeer over the top). Serve immediately.
Recipe by Darla