Apart from blue crisps, which I gave a recipe for last year, I've always struggled to find ways to cook those blue truffle potatoes. They aren't the only strangely hued spuds around, though: others have inspired me, too. On Tiptoe Farm in Northumberland Lucy Carroll grows long-lost heritage varieties with names such as Arran Victory, Shetland Black and Highland Burgundy. Many are burgundy, purple and bluish under their skins. When you buy a bag of her potatoes (01890 883060 or www. heritage-potatoes.co.uk tells you where or how to have them delivered to you) a tag tells you the year the seed was introduced. Many date back to the early 1800s, and Lucy's company, Carroll's Heritage, sources those old seeds. After years of nothing but King Edwards and Maris Pipers, which do their jobs in the roasting and mashing departments, some of these tubers take you back in time and give you a taste of the past.
You won't be surprised to hear that Tony Booth, my greengrocer friend at Borough Market, sells these potatoes, as do Turnips, another stall in the market. Tony suggested this combination of Arran Victory and crab in a salad, and I agree it's a great idea. Better still, I've added some of his punterelle, the spiky, bitter Italian winter chicory. If you can't get punterelle use dandelion or endive.
500g Arran Victory potatoes
1 head punterelle or endive
250-300g freshly picked white crab meat
1tbsp chopped chives, or fine chive tops
Sea salt and freshly ground black pepper f
for the dressing
1tbsp good quality white wine vinegar
Juice of half a small lemon
5tbsp rapeseed oil, or a combination of vegetable (or corn) and olive oil
A few sprigs of tarragon
Salt and freshly ground black pepper
Ideally, make the dressing the day before, by simply shaking everything together.
Cook the potatoes in their skins for 15-20 minutes until they are just cooked. Remove from the water and leave to cool, but don't refrigerate as they will lose their flavour. You can speed up the process by running them under cold water. Once cool, peel the skins away and cut them into rough 2cm chunks.
Remove the stalk from the punterelle and take out the heart. Save the outer leaves - they can be washed in ice-cold water, blanched and tossed in butter with pasta, olive oil and chopped anchovy fillets for another supper.
Soak the heart in iced water for 30 minutes to remove the bitterness, then cook it in boiling salted water for 3-4 minutes and drain and divide into 4. If using frisée or endive, just wash and dry the leaves. Arrange the potatoes and puntarelle on plates, season and dress well then scatter the white crab on top with the chives.