Cheese is glorious, but it’s also water disguised as joy. Use low-moisture mozzarella. Fresh mozzarella is a puddle waiting to happen.
Shred your own cheese. Pre-shredded bags have anti-caking agents that impact melting. You want oily, not gluey.
Quick visual: Imagine a pizza where the cheese slides off in one greasy sheet. That’s a horror movie. We want a symphony.