Good question! When baking a multiple-batch cookie recipe and you have 1 cookie sheet to re-use, cool (a few minutes in the freezer works) between batches or cookies will spread. Then use the touch test - if the cookie sheet feels greasy, use it without re greasing. Also see #5 of How to Bake the Perfect Cookie
for more tips about cookies.
Answered 12/21/2013 by Jeanie Kozar