Flash paper is another name for thin sheets of highly flammable nitrocellulose. When it catches light, it burns incredibly rapidly and very brightly, leaving nothing more than a trace of ash. Magicians often use it to provide a quick distraction during an illusion or to spice up an otherwise dull sleight of hand.
You can buy flash paper from any reputable magic shop, if such a thing can be said to exist. If you live in London, I recommend Davenports Magic
, an old family-run magic shop that has lurked in the basement of Charing Cross Station since 1898.
Flash paper is stored wet to avoid accidental combustion, so you'll have to dry out the required amount overnight before you use it for your Nuked Alaska.How to arrange your flash paper for a fireball
8 sheets of flash paper (~20cm square)
1 baking tray
2 disposable aluminium foil trays, smaller than your baking tray but with bases larger than 30cm x 15cm.
You don't want to have the flash paper touching your food and leaving chemical residue over the dessert, so it will instead be on a separate tray, surrounding the main dish.
Place one of the foil trays in the centre of the larger baking tray. Crumple seven of the sheets of flash paper so that they lie on the larger tray, surrounding the foil tray. Make sure that they are all touching, but twisting their ends together.
With the remaining piece of flash paper, make a thin strand that will lead from the larger tray to inside the baking tray. This will act as a fuse which will ignite the rum in the main central dish when the flash paper burns.Note that you will cook the Nuked Alaska in another aluminium foil tray, which you will then place inside the one you have surrounded by flash paper. This is to minimise the risk of accidentally igniting the flash paper by bringing it directly into contact with a hot tray.
Tuck the match head wrapped in resistance wire underneath the flash paper at one end of the larger tray and tape the connecting wires in place. You should now have a tray rigged to detonate in an incredible, but brief (and hopefully relatively safe) fireball.