When I think of Jersey, instead of potatoes and cream, I think of Bergerac and John Nettles. And Hasselback obviously sounds like Hasselhoff, so this recipe should be extraordinarily good at fighting crime.A good Maris Piper potato salad, dressed lightly with mayonnaise and chives, or new potatoes gently robed with a zingy vinaigrette always sit well on the summer table. Warm Anyas, butter melting and pooling around and tossed through with parsley, salt and pepper as well is a perfect side-dish with a barbecued and charred rib-eye steak or some grilled sea bass with a herby oil.This potato salad has the crisp salty crunch of delicious jacket potaoes. The ridges absorb all the flavours and juices. Let it sit a while before dressing so it cools down.The gribiche sauce is a classic normally served with veal's head. It's a kind of cross between egg mayo and tartar sauce. While that may not sound instantly appealing to some, it really is delicious and gives this dish a little twist.So the only crime worth fighting here is probably going to be the British summer. Oh well, maybe I'll have a Magnum anyway.Ingredients500g Jersey RoyalsOlive oilSalt to seasonFor the gribiche:2 egg yolksSalt to season2 cooled hard-boiled eggs (about eight minutes)5 cornichons1tbsp capers1 small shallot2tsp Dijon mustard1 small red chilli (optional)Olive oilRapeseed oilSome parsleyMethodHeat the oven to 180c.Score the tops of the potatoes all the way across the top a millimetre apart slicing down just a little so they look stripy.Put them on an oven tray and roll them about in olive oil and salt then roast for 45 minutes.While the potatoes are cooking, make the gribiche.Whisk the egg yolks, mustard, hard boiled egg yolks (keeping the cooked whites aside) and some salt together in a bowl then gently drizzle in the olive oil, drip by drip at first, whisking all the while until it starts to form a thick emulsion. If you have a mini food processor, by all means use it for this stage.Now switch to the rapeseed oil and continue until you have a nice pot of mayonnaise. Thin it down with a little water or lemon juice if you like.Finely chop the parsley, shallots, cornichons and chilli then lightly run your knife through the capers and dice the cooked egg whites.Add all of this to the mayonnaise then mix well. Taste and season more if you like.Let the potatoes cool just a little then stir through the sauce and serve.