What is the difference between Pizza Rosso and Pizza Bianca?

The most striking difference is that a rosso pizza has tomato sauce while a bianca pizza does not. Other than that, the toppings could be the same. In America, bianca pizza is often covered in lots of cheese. In Italy, it is often covered in olive oil and salt. Adding fresh basil, black olives, and fetta cheese to a bianca pizza is amazing IMHO.

Pizza rossa is a thin, tasty crust spread with savory tomato sauce; each good forno will have its own sauce, some more salty or herbaceous than others. Pizza bianca is a bubbly pizza crust topped simply with olive oil and salt. Again, each forno’s dough has its own taste and consistency, and is topped with more or less salt.

https://therovinglocavore.com/2010/01/17/rosso-or-bianco/