I give you quite easy tips for you when you travel Korea and you have no idea where to eat nice food. 

Just look for a big university. Popular and bigger university is better in order to avoid any failure.

And next?

Easy. 

Nearby the university, you can easily find MANY cheap and nice restaurants and cafeterias. Cause many university students live around there for their university. So that there's naturally lots of trendy restaurants. 

Ddeokbokki (떡볶이)

My favorite Strawberry cake !!