It's not really a secret -- they will make you anything you ask for. Don't expect every barista to know what a Butterbeer latte is, be prepared to order a tall whole latte, 2 pumps toffee nut, 2 pumps caramel, two pumps cinnamon dolce with whip and caramel drizzle (which, btw, I have tried and played with it until it tasted more like Butterbeer to me -- tall soy latte with 3 pumps toffee nut, 3 pumps caramel, add caramel drizzle, no whip). I also have a drink I call "cake in a cup" which is just a white hot chocolate with caramel drizzle.
Sent from me.