I updated the post to recommend parchment paper instead of greasing the cookie sheet and to mention that not all cookie sheets need the extra help. I haven’t tested this recipe specifically with a nonstick cookie sheet and the caramel can be quite sticky. Thanks for sharing your experience with copper cookie sheets!
If you have copper cookie sheets, you don’t need to grease them.
I updated the post to recommend parchment paper instead of greasing the cookie sheet and to mention that not all cookie sheets need the extra help. I haven’t tested this recipe specifically with a nonstick cookie sheet and the caramel can be quite sticky. Thanks for sharing your experience with copper cookie sheets!