Ground turkey burgers get a bad rap for being a little bit boring. But when dressed up with flavors of the Mediterranean like olives, capers, garlic and dill, and then stuffed with salty and tangy feta cheese, they become anything but. To maximize the flavor we made a quick tzatziki sauce and slathered it over toasted sesame buns, then topped the burgers with fresh tomato slices and crunchy lettuce.