Flat tarts like this are deceptively simple to make and utterly delicious. Use as much of the green part of the leek as possible, as it's full of flavour.
Serves 4
3 tbsp olive oil
60g butter
4 sprigs of thyme
Zest and juice of half a lemon
2 garlic cloves, peeled and crushed
80g whole hazelnuts
3 leeks, trimmed and finely sliced
400g Jerusalem artichokes, sliced into pound coin-thick circles
250g filo pastry
60g soft goat's cheese
1 Add 2 tbsp of olive oil and all the butter to a small pan over a low heat. Add half the thyme, and all the lemon zest and garlic. Cover and warm gently. If any butter solids come to the top, skim them off. Set aside until needed.
2 Preheat the oven to 200C/400F/gas mark 6. Toast the hazelnuts in the warming oven for a few minutes until light golden. While warm, wrap in a tea towel and rub them to remove the skins. Once cool, finely chop the nuts.
3 Add the remaining oil to a pan over a medium heat. Add the leeks and thyme leaves stripped from the remaining stalks, cover and cook gently for about 10 minutes until soft. Turn the heat up, add the lemon juice and stir. Let the leeks become pretty dry, season to taste, take off the heat and set aside.
4 Meanwhile, boil the artichokes in salted water for around 3 minutes until soft. Strain and run under cold water.
5 Brush a baking sheet with the infused oil mixture. Lay out one or two sheets of filo to create a 30cm square. Butter the pastry and scatter with a quarter of the hazelnuts, cover with another layer of filo and press down. Repeat to create three more layers on top of the first.
6 Cover the pastry base with soft leeks, then arrange the artichokes on top in overlapping rows. Season and brush with infused oil, crumble the goat's cheese on top and cook in the oven for 20-25 minutes until the pastry is crisp and the cheese has melted nicely.
7 Cut the tart into quarters. Serve with some bitter leaves dressed with orange.
• Rosie Sykes is head chef of Fitzbillies (fitzbillies.com) and co-author of The Kitchen Revolution (Ebury Press, £25). To order a copy for £19.99 with free UK p&p, go to guardianbookshop.co.uk
