Sorry to epic bump but I need help. Just came into possession of a 'summer truffle'. Was an impulse purchase just because I've never even seen one in real life before, never mind in Morrisons!
Now, what do I do with it? It has a hard outside like a lychee. Do I remove this? And then just shave it on stuff? How long will it last, as I doubt I'd be eating it all in one go...!?
First of all: think of it as like a highly delicious gremlin. DO NOT ATTEMPT TO WASH IT, or get it wet. Cut off the amount you intend to use in one go and wipe off any extra dirt with a brush or paper towel. Do not peel off the outside.
Secondly, DO NOT OVERCOOK IT. Truffles are all about highly complex chemicals which have a lot in common with human and animal pheromones (that's why people say they smell/taste like sex, because, uh, they actually do). As with coffee, there's a narrow range of temperature and treatment which will bring out the best in them. You can eat them simply shaved, but they need a touch of warmth to bring out the full glorious pong. So for instance you'd get a lot more out of shaving them over hot or warm pasta or risotto than over a cold salad. If you are going to cook them with other ingredients - like in an omelette or a risotto or potatoey bake - you want to add the truffles no sooner than 'just before the rest of the stuff is done'. If you overheat a truffle for too long you effectively just kill off the best niffs.
The lovely truffle reek will disperse into fats - so using plenty of butter or olive oil or cream or cheese in what you're cooking will stretch the flavour over more of a meal (or several). This is not the moment to rein back on extravagance.
One upside of the sickening cost of truffles is that they smell so strong they'll perfume other ingredients you store them with - so you can keep them in a little plastic / yoghurt pot of rice and it'll give the rice a detectable truffle flavour even if you cook it separately. This is also a good way to store a truffle (or a half-one if you leave any behind) because it makes it less likely to go (more)mouldy.
Some people store them with eggs and swear that the truffle aroma even penetrates the shells and leaves the eggs scented of truffles when cooked.
Truffles won't keep forever so check them daily for any signs of decay - and you'll probably have to eat it/them within 3-5 days of purchase, max. Oh what a torture.

(it has been quite a few years since I've had any).
Can you tell that I take truffles very very seriously?

at poncy self but they're really really special. It's not just a snob thing, or a weird-food one-upmanship, or blind conformism. if you're susceptible to them, they are just indescribably good. but (like any food) I've met some people who just can't see or sense what the fuss is about - lucky them, they get to save a fortune and leave the truffles for the appreciators.