Felicity Cloake’s perfect caponata. Photograph: Felicity Cloake for the GuardianAubergine is the star of this classic sweet and sour Sicilian vegetable dish – but the rest of the ingredients are up for debate. Are fresh tomatoes a must? And is it worth slipping in a bit of chilli or chocolate?Caponata, a lovely, piquant dish of stewed Mediterranean vegetables " and "one of the peaks of Sicilian cooking", according to Anna Del Conte " is a textbook example of the intense sweet and sour agrodolce flavours typical of the island. As Matthew Fort writes in Sweet Honey, Bitter Lemons: "Sicilian cooking embraces contrast, discord, counterpoint, counterpunching, variance and the absence of delicacy "... the dishes are as bold and baroque as any flamboyant building."
In keeping with this philosophy, caponata is a vegetarian feast to be reckoned with, a clear example of what Del Conte describes as one of the key characteristics of Sicilian cuisine, where "a simple local ingredient, in this case the aubergine, is taken as the basis of the dish, and is then embellished and enriched until the end result is an opulent and almost baroque achievement". In other words, until it's got more flourishes than a fancy palazzo.
However, Ruth Rogers and Rose Gray note warily in the River Cafe Classic Italian Cookbook that "there are as many ways to make caponata as there are cooks in Sicily", a fact confirmed by Giorgio Locatelli, who claims that "in every house and in every restaurant you will find a different version and opinion" " both facts to send a shiver down the spine of anyone not born in the shadow of Mount Etna. So, just how do the rest of us capture the essence of this bold and quintessentially Sicilian dish?
Aubergines
The River Cafe book informs me that "the basis of caponata is the popular aubergine" " and theirs is the only recipe to demand anything special in this department " "a large, pale aubergine about 12cm in diameter". I'm only able to lay my hands on the chalk-striped variety labelled "graffiti aubergines", which are indeed slightly paler inside, although I don't detect any difference in the finished dish. Rogers and Gray also require me to salt them before cooking, as do Del Conte and Locatelli, while Yotam Ottolenghi and Jacob Kenedy's Bocca don't bother. As in previous aubergine-related experiments, I find that there is no need to do so with the fruit we get here, which has had most of the bitterness bred out of it, but it does improve the flavour. (Ottolenghi salts after frying, which doesn't seem to work as well.) Del Conte and the River Cafe suggest half an hour, which proves sufficient.
Kenedy dices them into 1cm cubes, Ottolenghi 2.5cm. I compromise and choose Locatelli and Del Conte's 2cm cubes: too small and you lose the contrast between the caramelised exterior and the creamy inside; too large and there aren't enough pieces to go round. Ottolenghi and the River Cafe both shallow-fry their aubergines, while everyone else deep fries them. Shallow-frying aubergines is an endeavour bound to disappoint: as Norwegian food writer Andreas Viestad has pointed out, "a recipe that tells you simply to "pan-fry eggplant in oil' plays a cruel joke on a home cook "... before I knew better, I would start with a generous amount of oil, but the pan would be completely dry after a few seconds. When I added more oil, that disappeared, too, leaving me with the choice of pouring in even more or having some part of the eggplant cooked in a dry pan."
Aubergines are like sponges " sponges with a special affinity for fat. Mine soak up the 160ml of oil in Ottolenghi's recipe in seconds, leaving me with the dilemma outlined above. It's much better, in fact, to go with deep-frying; it's a bit more of a faff, but, as Viestad explains, the high temperature involved prevents the aubergine from soaking up too much of the oil, leaving it far less greasy than the shallow-fried version.
Bit players
Onion and celery are the other mainstays of caponata " indeed, Jane Grigson lists the latter as a main ingredient. I like the River Cafe's choice of red onion, which complements the other sweet flavours, but I'm less keen on the two whole heads of celery they use. To be honest, it's not my favourite vegetable, which may explain my preference for Locatelli and Kenedy's more moderate number of stalks. The River Cafe blanch theirs before use, and Del Conte deep-fries it, but it's just as easy to soften smaller amounts alongside the onion.
Locatelli explains that traditionally caponata "is made with whatever vegetables the people have, depending on the season"; he uses courgette and fennel, while Ottolenghi adds a red pepper. This, of course, gives you carte blanche to substitute whatever you fancy; personally, I find the pepper has a tendency to overpower the softer, creamier flavours of the other vegetables, and I'm not particularly keen on mushy fennel, but the courgette works beautifully. Garlic, for once, doesn't add much to this recipe " the River Cafe and Ottolenghi use it, but I can't taste among all the other flavours in there.
Tomatoes
Although none of the caponatas I try are exactly swimming in sauce, some are more tomatoey than others, with Del Conte, Ottolenghi and Kenedy's versions far richer and redder than Locatelli or the River Cafe's. Kenedy uses fresh tomatoes, the River Cafe fresh or tinned, Locatelli fresh plus a dash of passata, Ottolenghi tinned and Del Conte passata. Obviously, Sicilian tomatoes are more reliably ripe than I can find, so I'm going to go down the Locatelli route and use a mixture to ensure the other ingredients " including chunks of juicy, fresh tomato " get a rich, jammy coating.
Salt, sour and sweet
Fort's claim that "the sophistication of Sicilian cooking lies in its ability to take in extremes and create dishes that assault perceptions of taste" is backed up by the riot of flavour that characterises the caponata. Not content with the oily richness of fried vegetables and their tangy tomato coating, most caponatas also contain a salty element from olives, capers or even Kenedy's anchovies; something sweet, in the form of sugar or sultanas and raisins (an inclusion that owes a lot to the Arab influence on the island's cuisine); and a balancing sour ingredient, such as red wine vinegar or Ottolenghi's lemon juice.
I love the little pops of sweetness that the dried fruit provides " whether you'll need any additional sugar depends on the ripeness of your tomato " especially when it's countered with a hefty slug of vinegar: the modest 2 tbsp in the River Cafe recipe is far too subtle when you've tried Del Conte's version that uses five times as much. Capers are a must, and I think the cleaner saltiness of Del Conte and Ottolenghi's green olives are a better fit than the richer, earthier black version in Locatelli's dish.
Sicilian food is also distinctive in its use of spice " the River Cafe crumbles in two chillies, while Ottolenghi takes the island's history literally and stirs in some harissa. The acid heat is welcome with all that oil, but you can leave it out if you'd prefer, since it doesn't seem to be canonical.
Two unusual twists to note: Kenedy adds a little orange juice, Del Conte grated dark chocolate. I can't detect the former, but I can pick up the bitterness of the latter, which adds yet another layer of delicious complexity. And if you can put coffee in chile con carne, why not chocolate in caponata?
To finish
Ottolenghi and Kenedy finish their caponata with parsley, the River Cafe with mint and Locatelli with basil. All bring something different to the dish, and I'm surprised to find I like the fresh sweetness of mint better than the slightly aniseedy one of basil or the pepperiness of parsley. Locatelli, Kenedy and the River Cafe also add a little crunch in the form of pine nuts, but a chance comment from a friend newly arrived home from Sicility suggests flaked almonds are more common on those shores " and, crisper and sweeter, I like them even better here. Locatelli stirs in some croutons, and the River Cafe suggests serving their caponata on toast. Traditionally, this is often served as an antipasto with bread, but the croutons are another option if you'd prefer to have it as a salad, panzanella-style.
Cooking
Kenedy bakes his caponata for an hour after frying, while Del Conte allows it to stew for 30 minutes, Ottolenghi 10, the River Cafe five. Locatelli doesn't cook it further at all, instead allowing the warm mixture to "infuse" for two hours under clingfilm. While I don't think you need to turn the oven on for this dish, the longer the cooking time, the deeper the flavour.
Finally, like many dishes, caponata tastes much better at room temperature " or barely warm " than hot from the oven. If you can leave it to mellow for a few hours, so much the better.
Felicity Cloake's perfect caponata
(Serves 6-8)
1 large aubergine (about 500g), cut into 2cm dice
1 large courgette, cut into 2cm dice
Salt
Vegetable or sunflower oil, to fry
3 tbsp olive oil
1 large red onion, sliced
2 celery sticks, cut into 2cm dice
1½ tsp chilli flakes (optional)
150g ripe tomatoes, diced
40g capers
40g green olives, stoned and quartered
40g sultanas or raisins
1 tbsp sugar
150ml passata
100ml red wine vinegar
1 tbsp grated dark chocolate
40g toasted almonds or pine nuts
Small bunch of mint, leaves picked
Lightly salt the diced aubergine and courgette and put them in a colander over a sink, trying to keep them in two distinct layers. Leave to sit for at least 30 minutes, then pat dry.
Heat a wide, deep pan one-third-full of vegetable oil until it reaches 190C, or a breadcrumb dropped in browns immediately. Fry the aubergine and courgette in batches (being careful not to overcrowd the pan) until golden, allowing the oil to come back up to temperature between frying. Drain on kitchen paper.
Heat the olive oil in a large, wide pan (for which you have a lid) over a medium-low heat; fry the onion and celery with a pinch of salt until soft and beginning to colour, then stir in the chilli, if using. Fry for another minute, then add the diced tomatoes and fry for another couple of minutes.
Stir in the capers, olives, sultanas, sugar, passata, vinegar and chocolate and bring to the boil, then add the fried vegetables. Season, turn the heat right down, cover and simmer gently for an hour, checking towards the end of cooking and taking the pan off the heat if it seems to be drying out.
Take off the heat and allow to cool to room temperature, then check the seasoning. Meanwhile, toast the almonds in a dry frying pan, then add them, along with the roughly torn mint, just before serving.
Caponata: on crostini, with couscous or pasta or even in a cheese sandwich, " la Ottolenghi: how do you serve this sweet-and-sour Sicilian classic? And what other ideas can you come up with for the awesome aubergine?