When making brownies, how do you prevent them from sticking to the pan?

I have made brownies (always from a mix) and let them cool in the pan, because if I try to cut them too soon, they break up. However, when they cool in the pan, they’re often hard to get out. They taste good, not burned, but the outside edge I often have to give up and chisel out the inside part.

Pan will be sprayed with Pam first, so it’s not like it’s not prepared.

Will parchment paper work?

How do I prevent brownies from sticking too much in the pan?