I'm not sure exactly how I came across them, but I first watched Love Letter and X-man. I didn't really know who was who back then, but I really liked Park Soo-jin (time to Google her and see if she was in any movie/dramas lately!).
I was still more into Japanese entertainment at the time, but Korean movies/dramas started booming and naturally sparked interest in their idols/actresses. I think after Love Letter/X-man, I randomly stumbled across Family Outing S1 (because of Kim Tae-yeon), Invincible Youth S1, We Got Married, and a lot of other shows. Now, the variety show that I look forward to every week is Running Man.