Tip: The slow-roasted tomatoes can be done the day before, or pop them into the oven a couple of hours before you start the rest of the dish.
Recipe by James Martin, taken from Saturday Kitchen Cooking Bible (£20; Weidenfeld & Nicolson)
- 6 tomatoes on the vine, halved widthways
- 4 tbsp olive oil
- 4 sprigs thyme
- sea salt and freshly ground black pepper for the tart
- 5 tbsp olive oil
- 450g waxy potatoes, peeled and sliced thinly
- 6–8 fresh sardines, cleaned and butterflied
- 10 oregano leaves
- sea salt and freshly ground black pepper
Preheat the oven to 150°C/300°F/Gas 2
Place the tomatoes, cut-side up, onto a roasting tray just big enough to accommodate them. Drizzle over the olive oil and sprinkle with the thyme, sea salt and freshly ground black pepper. Place in the oven and slowly roast for 2–3 hours until the moisture has mainly evaporated and the tomatoes have dried out
Remove the tomatoes from the oven and set aside to cool. Turn the oven up to 200°C/400°F/Gas 6
Heat a medium-sized (about 25cm) ovenproof frying pan over a medium heat then add a drizzle of the olive oil. Arrange the sliced potatoes in overlapping circles so they cover the bottom of the pan. Season with salt and pepper, then turn the heat down to low. Cook for about 5 minutes until the potatoes turn golden-brown at the edges and are translucent in the middle
Place the sardines on top in a fan shape, with the tails pointing towards the middle of the pan. Drizzle with the olive oil and season with a little more salt and pepper
Lay the oven-roasted tomatoes over the top then sprinkle with the oregano. Bake in the oven for 15–20 minutes until the potatoes are cooked and the top is golden brown. Remove the pan from the oven and let the tart cool slightly.
To make life easier, get the sardines prepared for you at the fishmongers.