What's the best hamburger restaurant of the city?

Good evening, folks!
My partner and I would like to go out for some burgers and fries. Could you recommend the best places in town? I'm Italian, so I’m familiar with McDonald's and Burger King, which we’d like to avoid. The only requirement is that the menu should offer both vegetarian and meat options, and if the burgers are big, even better!
Thanks in advance!