I heated up a cast-iron pot in an oven and might have burnt the lid. Is it possible to restore it back to its formal glory?
That is an enameled cast iron pot. I often have the same issue and find that it fairly easily comes off using a green 3M nylon scrub, a little dish soap and some elbow grease. If necessary you can also apply some baking powder or Bar Keeper's Friend.
It shouldn't take too much effort to get it off.