Valentines day part 2

I used a simple peanut butter cookie recipe and bought chocolate hearts to place on top. One lesson I learned is the hearts may look cooled but they are probably not. Since the hearts are placed on after the cookies come out of the oven the don't look warm but the cookie warms them enough so when u place the heart on top it melts a little to stick also the heart is soft and shouldn't be touched until it is completely cooled.