9/10 is my rating. This is a 2007 South Korean television series that spanned 17 episodes (~60 minutes/episode).
Go Eun-chan (Yoon Eun-hye) has always been a tomboy and is often mistaken for a man. So when a job with a new coffee cafe becomes available but is only open to men it is an easy role for her to fill - pretending to be a guy. Choi Han-kyul (Gong Yoo) has always been a rick playboy. His grandmother forces him to start a business in order to get him to take things more seriously. A "bromance" turns romance develops between the two main leads.

Spoiler ? I liked this one a lot. I felt incredibly bad for the male lead as he struggled with having feelings towards what he thought was a guy. I also liked all the supporting characters and their reaction to the "female" lead. It was well acted, well scripted, just all around enjoyable. For me a 9/10 just because I did feel like there were some slow parts.