As far as I know, the only difference between white pizza and red pizza is the sauce.
I know that the white sauce is dairy-based, but what is it exactly? What are the main ingredients, is it thickened somehow? Is there something special to pay attention to when making white sauce? How thick should it be exactly? Should it contain herbs or not? Oil? How does it combine with the cheese, is the cheese supposed to melt "into" it?