Olive oil has been a staple of Mediterranean cooking for thousands of years. Mark Hix rolls out the barrel with a fresh set of recipes

Olives are so much a part of the Mediterranean landscape, it's impossible to imagine a scene without an olive tree in it, or a bowl of glistening olives on a dining table. Oil has been extracted from olives for tens of thousands of years, and it's equally impossible to imagine cooking without it now.

Olives are so much a part of the Mediterranean landscape, it's impossible to imagine a scene without an olive tree in it, or a bowl of glistening olives on a dining table. Oil has been extracted from olives for tens of thousands of years, and it's equally impossible to imagine cooking without it now.

Yet I must admit I didn't really appreciate the olive until I was well into my career and the Mediterranean boom hit London. I can't recall ever even trying one until I was in my teens, and even then I thought they always came in jars with little bits of red pepper in the middle. Like anchovies and capers, olives can be one of the trickier foods to tempt young ones with. I don't suppose it would help if you told them that its importance as a soothing ointment and source of food gave the olive religious significance. In the book of Genesis, the dove brought an olive branch back to the ark, thus proving that the waters were subsiding after the flood.

These days, olive oil is worshipped in a different way in foodie circles. There's a lot of olive-oil snobbery about, and foodie households keep an array of estate-bottled oils from Spain, Italy, France and Greece for anointing their food. For all the fuss made of the finest Italian olive oil, which they talk up in the grandest and most passionate of terms, most years Spain tops the worldwide production charts.

The Greeks introduced the olive to Italy and in turn the North Africans brought it to Spain. The Romans once again put their practical skills to work, invented the screw press and perfected the method of extracting juice from olives. They were also responsible for spreading olive groves to northern Italy and even Provence. Even with olives growing in almost every province of Italy, they couldn't keep up with demand for the holy oil and had to import it from Spain to fulfil their needs. It still happens to this day.

Good Spanish oil is making its presence felt, and oil is also appearing from all sorts of other places including Argentina (see Food Notes, page 55), Syria and Australia. Like wine, the quality of the oil can vary from season to season, so your favourite single-estate oil may not make the grade every year. Only about 10 per cent of the world's olive oil is the best extra virgin. Some extra-virgin oils are sold unfiltered, giving them a cloudy appearance. Flavour, aroma and colour must be top class and the acidity level no more than 1 per cent.

Virgin olive oil, with an acidity level of not more than 2 per cent, should still have a great aroma and flavour, but it's not the very top grade. Oil described simply as olive oil is a blend of refined and virgin oil. Refined oil has no taste or smell and the virgin oil is added to give a little flavour. Save your extra-virgin oil for salad dressings and drizzling, your virgin for cooking and keep olive oil in the bathroom cabinet - where olive oil used to belong when I was growing up.

Insalata bianco

Serves 4

Just for a change why not have a salad that's completely white? Along with fennel, chicory (Belgium endive) tends to be overshadowed by lettuce in most fridges. But they're both great eaten raw in a salad, especially with a slightly sweet dressing. Here, with white balsamic vinegar and oil, they make a lovely white threesome with Pecorino or Parmesan cheese. If you can't find white balsamico, which is available in most Sainsbury's, use a good quality white-wine vinegar like Chardonnay.

1 head of fennel
2 heads of chicory
50-60g aged Pecorino or Reggiano Parmesan
Salt and freshly ground white pepper for the dressing
2tbsp white balsamico
8tbsp extra virgin olive oil

Peel the outside of the fennel with a potato peeler if it looks stringy then cut it into quarters and remove the root. Shred it as finely as you can, wash it briefly and drain in a colander. Remove any discoloured outer leaves from the chicory and cut the root end off to release the leaves. Separate all the leaves into a bowl, wash briefly and drain with the fennel. You can dry these in a salad spinner if you have one.

Meanwhile make the dressing by whisking the vinegar and oil together and seasoning. Dress the chicory and fennel, lightly season and arrange in bowls or on plates. Shave the cheese over the salad with a vegetable peeler, mandolin or cheese slicer.

Fillet of wild sea trout with asparagus

Serves 4

Using olive oil can be a tasty alternative to poaching in water or a court bouillon. The oil is then used in the dressing and sauce, so it's not being extravagant with it. Any leftover oil can be strained, frozen and used again several times. This recipe is simple and seasonal and doesn't involve ages spent over the stove. Use as many types of asparagus, and samphire, as you can get your hands on. I've used sprue and corn ear asparagus here but you could use thicker green, wild and white. A good fishmonger should be able to get wild sea trout for you, otherwise you could bite the bullet and use salmon - try to find organically farmed.

4 portions of sea-trout fillet weighing about 160g, skinned and boned
150-200ml olive oil plus 150-200ml vegetable oil or enough equal amounts of each to cover the fish
1tsp fennel seeds
1 bay leaf
A few sprigs of thyme
10 black peppercorns
2tsp sea salt
12tbsp chopped chives
12tbsp chopped chervil
12tbsp chopped parsley
250-300g sprue asparagus, woody ends trimmed

for the sauce

1 egg yolk
1tsp good quality white wine vinegar
150ml strained oil from cooking the fish
1tbsp water
Juice of half a lemon
Salt and freshly ground white pepper

In a pan large enough to fit the fish, combine equal amounts of olive and vegetable oil with the fennel seeds, bay leaf, thyme, peppercorns and salt. Heat the oil gently over a low heat for about 5 minutes then remove and leave to cool and infuse for 30 minutes.

Warm the oil up again on a low heat for 5 minutes, then immerse the sea-trout fillets in the oil and return to a low heat and cook them for 3-4 minutes. Leave to cool in the liquid. This should keep the trout nice and pink, if you want it well done, which I wouldn't recommend, then cook it in the oil for a couple more minutes.

Meanwhile cook the asparagus in boiling, salted water for 2-3 minutes, or until tender. Remove with a slotted spoon and plunge into cold water for a minute before draining in a colander.

Remove the sea trout from the oil and put the fillets on a plate. Strain about 150ml of the oil into a small jug. Put the egg yolk into a bowl and whisk it with the wine vinegar then gradually trickle in the strained oil, whisking continuously until all the oil has been added. Whisk in the lemon juice and season with salt and pepper if necessary.

Strain another 3 tablespoons of the oil into a bowl with the chives, chervil and parsley, and season with salt and pepper. Mix two thirds of this oil with the asparagus and arrange on plates. Put the sea trout on top and spoon over the rest of the oil. Serve the sauce separately with some hot, buttered Jersey Royals.

Olive oil cake

Serves 6-8

Olive oil, instead of butter, is used for baking in countries where there's plenty of it. It makes the cakes dense and rich and faintly fruity. I'd been experimenting with recipes for a cake made with olive oil and just couldn't get it right, when photographer Jason Lowe came to the rescue with this recipe. He has a home in Tuscany and can get hold of a very fruity olive oil produced nearby. I made this cake with my daughters Ellie and Lydia and it went down a treat with some raspberries and a good dollop of whipped cream. Well, it's one way of getting them to appreciate olives, I suppose ...

300g caster sugar
3 eggs
300g plain white flour sifted with 1tbsp baking powder
Grated zest and juice of 1 orange
Grated zest of 1 unwaxed lemon
120ml extra-virgin olive oil
100ml milk

Pre-heat the oven to 180ºC/gas mark 5. Whisk the sugar and eggs together until light and fluffy - in a food mixer if you prefer. Add the juice and zest of the orange and the lemon zest and then stir in the olive oil and milk. Gently fold in the flour and transfer to a lightly greased (you can use olive oil if you wish) round tin about 20-24 cms in diameter (you can use a square or a loaf tin of similar size).

Bake for 40-45 minutes. You can test by inserting a skewer or something similar and it should come out clean.

Leave to cool in the tin then turn out onto a cooling rack and leave to cool. Eat for tea or as a dessert with mascarpone, whipped cream, crème fraîche or ice cream, and raspberries.