Just made pear&ginger upside down cake for SIL's birthday tea tomorrow, wasn't cooking so ended up baking it for twice as long. My knife came out clean but because it took so long I gave it an extra five minutes to be safe. It came out very cleanly BUT the very top (where the fruit is) is only half baked and very runny. Can I stick it under the grill to finish it off?! Please help!!!