@anatman I'm still working on that part. The blueberry is probably a syrup, so the Lemon bit probably is too.
OK, I'm starting here. Just waiting for the syrup to finish cooking and then cool:
https://www.driscolls.com/recipes/blueberry-lemon-syrup
Then it's gonna be blueberry lemon latte time.
@butch how do they do that without the lemon curdling the milk?