I don't know why you'd want to mess with a perfectly good breakfast like cold leftover pizza. But if you do, here's a video that shows you how to turn those cheesy slices into french toast.
Chef Internet Shaquille describes his gluttonous creation:
When you French toast leftover pizza, the stale crust becomes a soft and savory pillow, while the once-rubbery cheese crisps on the outside of a gooey interior. This isn't a technique you want to waste on artisanal thin-crust gouda slices. In fact, it works best on cheap doughy brands like Domino's.