As all aircrew should know (?). If you pass a fast moving stream of pure oxygen over grease then it can cause it to catch fire. (Its a warning when using the oxygen bottle refill points in an E-3D - check for grease contamination before filling the bottle). I heard the story about the Nav, on QRA in the back of an F4, who dropped his oxygen mask to take a bite out of his cheese sandwich, only for it to spontaneously catch fire (no doubt the grease in the cheese or the butter took exception to the pure oxygen). I always wondered if this was true, but I always used it as an example of why the E-3D Warning was there.
I wonder how much fat was in the chocolate teacakes?
On a different subject... many years ago I was on South Harris in the Shetland Islands and met one of the Islanders who heard the crash of the Shackleton into a mountain on the island in 1990 and went with some of his colleagues to investigate. The group hurried up the side of the mountain to find the crash site - the first thing that they noticed of the wreckage as it loomed out of the mist was a Dairy Cream Sponge just laying amongst the heather. The crew was between tasks at the time of the crash and no doubt were having their mid-sortie meal.