Jerusalem Artichoke Gratin

Jerusalem artichokes aren't from Jerusalem and they're not artichokes but other than that whoever named them hit the nail pretty much on the head.  Reputation of their flatulence inducing properties, coupled with the fact that in their raw state they look more like something's gone terribly wrong at the potato farm means they're sadly under-appreciated by your typical home cook.  This is a great shame, they're versatile and delicious, tasting similar to artichokes but with a more gentle and subtle savoury taste that means they can work very well with other flavours in a meal (rather than turning them into a car-crash as artichokes can do.)  This recipe uses them to liven up a simple gratin into a much more interesting dish, it's also a rather sneaky way of introducing a few of them into a meal in a way that won't have people pulling faces and claiming squeaky bums in the manner that might greet a big bowl of roasted Jerusalem artichokes or a Jerusalem artichoke soup, which are more popular ways of serving them.

I think the farting effect is exaggerated, mainly because we all like to make bottom-burp jokes.  It is something that only afflicts certain people, it's not the case that everyone gets the almighty trumps after eating a bit.  Jerusalem artichoke's main carbohydrate is inulin rather than starch which some people can be very intolerant to, causing "a filthy loathsome stinking wind in the body" as a 17th Century gardner put it.  The inulin content is nothing particular to Jerusalem artichokes though, chicory, onions and garlic for example all contain it in high concentrations.

Ingredients


1 large potato
6/7 medium Jerusalem artichokes
5 or 6 slices prosciutto
parmesan cheese
1/2 litre stock
nutmeg

Put the oven on at 180 degrees.  Peel the potatoes and the artichokes and then slice as finely as possible.  I use a mandolin for this which is quite good fun but bloody dangerous when you're getting down to the last bit of a vegetable (if your concentration slips then your finger slips then eeeuuuwwww) if you've got a food processor with the right attachment use that, otherwise you'd better enjoy (like, really enjoy) using a knife to chop things 'cos it's a lot of chopping.

Grease an ovenproof gratin dish with butter (or oil) and place a layer of potato and artichoke slices in the bottom, grate a little bit of nutmeg over and season with salt and pepper.  Go easy on the salt, you might even want to omit it altogether since the ham and the cheese are both quite salty and depending on the stock you're using there could well be enough salt in the dish already.  Add some torn/snipped pieces of prosciutto and grate a bit of the cheese over that, dot a little bit of butter on it if you're feeling really decadent and repeat to build up each layer in the gratin dish.  Pour the stock over, grate a little more cheese on top and place the covered dish in the oven for about an hour.  After an hour remove the cover, turn the over up to 200 and give it another 10 or 15 minutes to crisp up a little on top.  

Jerusalem artichoke flower photo courtesy of KingsbraeGarden