Help identify pizza found at Washington Sq. Park

I wanted to add a picture but I can't! 😓 It's a rectangular slice, thick, with caramelized onions, sweet yet tangy from the cheese, likely a sharp type of cheese (not yellow in color like cheddar). I (dumbly) didn't look at the box to identify where it's from. I think it's definitely not Joe's. The place they bought it must have been nearby the park. I absolutely need to have this pizza again!!! Pleaseee recommend if you know a place that sells rectangular caramelized onion pizza, preferably near Washington square park 🙏🏻

Edit: thank you so much everyone!!