Now that I think about it, I believe I've never played a chess tournament without a cup of coffee at my side. As a young player without much money, we would ride together in someone's car and pick up coffee at fast food places like Jack in the Box. Back then, it was cream, no sugar.
Now, I usually make my own or stop at an always available Starbucks. I prefer Peet's, but I can't always find one. The quality of coffee is much higher now than it used to be, so I always have it black. Why buy an amazing Ethiopian coffee just to muck it up with cream and sugar and turn it into some kind of liquid candy?
Coffee is a performance enhancing drug that rarely gets you in trouble with the doping authorities. But coffee varies considerably in taste and additives. When you are playing in a chess tournament, do you stop at Starbucks, Caffé Nero, Thomas Hammer, or some other espresso bar enroute, or do you prefer the drip coffee served by tournament organizers? Do you use cream? Do you use sugar? Do you use flavoured syrups?