My friend April, who’s the chef at the Spotted Pig gastropub in New York, serves these with her famous blue-cheese hamburgers. She calls them shoestring fries, but in classic old-English game cooking they’re called straw potatoes. They’re a pretty common side dish to roasted grouse or partridge, or you might have game chips or pommes gaufrettes (which are comparable to crinkly chips). By cutting the potatoes in this recipe nice and fine – around 0.5cm thick – you can cook them until golden and crisp first-time round in a fryer or large pan of frying oil. For the last 30 seconds, I like to put a nice big handful of rosemary in with them – this will flavour the oil and the potatoes in the most incredible way.
A quick word about deep-frying: don’t disregard the importance of being incredibly careful and remember a) not to leave the pan alone as it might catch fire and b) not to leave kids in the same room on their own with the pan.
To make your lemon salt, bash and mix together the lemon zest with the salt in a pestle and mortar or Flavour Shaker until the salt is flavoured, coloured and fine. Place in a dish. Use whatever you need straight away or allow it to dry out for a couple of hours before storing it. It might go hard, so just crush it up a bit before putting it into a jam jar.
Heat 6–8cm of sunflower oil in a sturdy pan and bring to deep-frying temperature. You can do this by using a thermometer, or by placing a small chunk of potato into the cold oil before you begin to heat it. When the potato is floating and a dark golden brown, the temperature will have reached 180ºC/350ºF/gas 4 and you’re ready to begin frying (remember to remove the piece of potato before you begin).
Pat the julienne strips dry with some kitchen paper to remove any excess starch. Making sure you’ve got a slotted spoon or spider (which is like a flat colander with a handle) and a big pile of kitchen paper to one side, carefully place some of your potatoes into the pan of oil (don’t overcrowd it) for a couple of minutes until golden brown and crisp. Cook the potatoes like this, in batches, until they are all used up. Add the rosemary for the last 30 seconds. Remove the chips and rosemary to the kitchen paper to soak up any excess oil, and then dust with your lemon salt. Serve straight away.