I did the same thing...answer I found: turn the Oven temps down to 450-475 degrees.I have noticed with my pies,if the temp are 500+,the cheese wont last at more than 5+ minutes,then after that,they break down and burn or become a blistering goo...While you are doing the Varasano dough recipe,he was cooking his pizzas in temps that were in the 800+ degree range using the cleaning cycle.
Those high temp pies can cook in 2 minutes or less!
With my stone and electric home oven,I pre heat the oven to 550 for about 45 minutes or so...then I turn the knob down to 450-475...then about 15 minutes later,I cook the pizza.
Right around there.This gives the crust ample time to cook while the cheese melts.You may need to adjust your cook temps until you find YOUR sweet spot where it comes out perfect for you.It took me quite a few times before I got it right.
My oven,and your oven,may not be at the same temps per where we press the button or turn the knob.
I made 2 pizzas tonight...both the exact same way and same sauce,cheese,etc.One was cooked at 550+ and the other was done at 475.The difference was night and day.
I took pics but I cannot post it yet...but the hotter pizza,the cheese broke down and had burn spots...the color became a dark orange under the cheese.Yuck.
The 2nd pizza,lowered temps,the crust cooked nicely,not charred burnt,but in between...the cheese melted white and stayed white after I took it out of the oven.I do admit the crust color was a little lighter than Im used to but it was indeed cooked.
It can be reheated up as well...I will try to get some pics posted within the day or so.
Before I go,someone on here once told me alot of NY style places,that uses Deck ovens,run under 500 degrees.It is not uncommon to see a NY style pizza place with a Bakers Pride deck oven,running around 450-475 or so.Deck ovens use stones in them to cook the pies.