Italian burger help please?

I have to make a burger for school, so i'm going with an Italian theme. I'm using ciabatta bread, a beef pattie with oregano and red bell pepper in it. But i'm not sure what kind of cheese i should use? also what veges? i was thinking red bell pepper, but should i grill it or leave it fresh? and what other veges could i use? I'm also using basil pesto as a dressing.