How can I unstick two pans that are stuck one inside the other?
Submerge both pans in very warm water. When they expand from the heat they should come apart.
Try putting them in the freezer for a few hours.
You grab the one inside of the other (well at least try to if you can) then Ask some one to hold the other then pull on it... but not hard cuz if it comes out then one of you might get hurt.
Spray some Pam on them and see if that works them loose.
Find something thin to slip between the pans and use it as a wedge.