I've never been in Korea, but I've watched a lot of videos on Youtube that made me discover many snacks I would like to taste.

"Chocoheim" cookies seemed very yummy, they are sticks similar to a Twix bar but I don't know with what are they filled. And then I seen some puffed rice snacks and caramel in a yellow packaging. Very interesting :)

I like chocopies, veggie chips, and melon bars^^

i love Pepero (빼빼로) ^^ it like "must have" snack in my bag kkkk and about drink it's a bit confusing.. i usually order Pat Bing Soo when hang out with friends~ but it kind of dessert i think

Like many local people, when I was in Korea I prefered imported snacks (USA, EU) because their ingredients were easier to understand, their packaging was minimal, and they tasted better:

http://www.koreabang.com/2014/stories/korean-consumers-fooled-by-deceptively-packaged-snacks.html