Chocolate covered cookies stuck to cooling rack
Turn the rack upside down, suspend it so that there is about a quarter inch between the cookie and the surface it will fall onto when it detaches from the rack, then heat the chocolate underside of the cookie (which is now the top that you can see because the rack is upside down) with a hairdryer/low temp heat gun so that it melts enough for the rack metal to move through the chocolate and for the cookie to fall/push off the rack