Big Slice Pizza on Haight Ashbury serves just that in its name, a big freaking slice of pizza. They provide huge slices of pizza topped with stomach-filling toppings like the pesto and potato pizza and meat lovers. Pizza lovers can grab a seat in their quaint dining area or grab their slices and eat on the go. Big Slice Pizza is open late nights for those guests that want to get a quick bit to eat after the bars have closed on Haight Ashbury.