Homework:What's your favorite junk food?

Though I don't like junk food much, I really like coke. It's more than "like" I'm almost addicted in it. Nowadays I drink less than before, but just before few years, I usually drunk 200ml of coke every meal. I know It's harm to my health, so I drink sparkling water instead of coke. I heard sparkling water is not good to my stomach, just like other soda, but there is no sugar, so I think It's better than soda.
And If junk food means only foods, not include drinks, than I will choose a hamberger because It's not expansive and some times I eat that when I don't feel like to eat korean foods.