Hamburgers with Feta and Caramelized Onions

I am back from my vacation. Although we never made it to the mountain for skiing, I had a wonderful time with my family and friends. It's good to be home and great to be cooking again.I was craving a hamburger but didn't want an ordinary burger. I thought adding some feta cheese and a few herbs would make these burgers taste fantastic. I was right! The feta bits caramelized while cooking and