Long story short:
There's a coffee shop in one of the downstairs store spaces of my apartment building. This is where I go for my morning joe before work practically every day. My drink of choice? An iced mocha with skim milk. Mochas are pretty well-known coffee drinks (or, at the very least, they are where I'm from) and it typically goes without saying that the mocha part of the drink is mocha syrup. Especially since 9 out of 10 employees in this shop make this drink with mocha syrup and since the menu says that's what it's made with.
However, there's one employee who, for the longest time, kept giving me mochas that tasted like, well, to be blunt? Crap. I mean truly horrible and undrinkable coffee. I couldn't figure out what the problem was, especially since everyone else there made the most delicious coffee. Of course, one thing I did tend to notice was you could sometimes see streaks of mocha syrup in the coffee made by other employees. So, one day, I tried to be wily and watched what this guy was doing when he made my drink.
Instead of putting mocha syrup into the drink --- again, like the other employees do and the menu says to do --- he put in a scoop of Nesquik powder.
At least it explained why the coffee tasted so bitter.
Since then, whenever I see that he's the one who's going to be making the espresso drinks while I'm ordering, I try to order something else. Of course, sometimes this slips through the cracks since I'll think someone else is going to make the drink and he jumps on the espresso machine instead. And, hey, for all I know, that's how he likes his mochas and he thinks he's doing me a favor by making it that way for me. But it's sort of a pain in the butt and I'm not really sure how to go about pointing out that the drink I'm ordering requires syrup not... a scoop of powdered chocolate.
I really don't want to say anything that could be construed as rude in this place. Like I said, the employees are all really nice and I go there all the time. But I also sort of want the drink I ordered in the morning. Any suggestions on how to politely point out that he should be making the drink a different way?