In tests completed by the Western Dairy Center at Utah State University, scientists found that the stretch quality of mozzarella cheese decreased when it got too hot.
Waiting for your cheese to cool to the optimal temperature range will significantly increase your pull, but waiting too long and letting it cool too much is disastrous.
Allowing your cheese to melt at the low side of medium heat also creates a gooey cheese pull. The maximum melting rate occurs between 265 and 320 degrees Fahrenheit.
This process happens within three to four minutes. When the cheese is thoroughly melted, remove it from the heat and allow the cheese to cool to 145 – 150 degrees Fahrenheit.