The result is crust that blisters nicely in the coal-fired oven.
One reason for that is the use of a coal-fired oven, which generates far more heat than most gas or electric installations.
New Haven-style pizza is traditionally baked in a coal-fired oven and is sold whole rather than by the slice.
No. 2 Furnace was erected in 1842, using waste gas from the stack to heat the blast instead of coal-fired ovens.
That's not to mention the coal-fired oven that was installed 49 years ago.
There is no single feature that characterizes it (not even the use of a coal-fired oven).
Patsy Grimaldi's coal-fired oven is getting a fresh brick facing, and his restaurant will reopen this week.
It is thin-crusted and traditionally cooked in a hot coal-fired oven to a charred, smoky crispness.
"It has one of the few coal-fired ovens left in the city," he said.
Around the corner is Lombardi's, a 95-year-old pizza shop with coal-fired ovens.