There are those commentators who insist that you cannot cook a perfect tortilla unless you have the fiery blood of Spain coursing through your veins. But it can be done by us extranjeros: all it takes is a little patience, some careful timing and a whole new approach to the cooking of potatoes.

Firstly let me say that I am an advocate of the less is more approach to cooking this tapas bar classic. Who knows if the new wave of Spanish chefs are right now at work on a second generation of tortillas, conjured from dreams and childhood memories, but dispensing with such trivialities as eggs and potatoes? If you want to impress your Spanish friends with the authenticity of your cooking, leave out all extraneous additions, the only exceptions to this rule being a little finely chopped onion and perhaps just a sliver or two of garlic.

In the time honoured fashion I will start with the Ingredients:

• 4 large, free range eggs
• 6 smallish potatoes (new potatoes are good)
• 1 small Spanish onion – finely chopped
• 1 clove of garlic- finely chopped (optional)
• A good pinch of table salt
• A cupful of olive oil.

The first job is to peel and finely chop the onions. Red onions are a good choice here as their sweetness adds a little extra to the final dish. If you are using garlic, take your time and slice it as finely as you are able. Any Spanish chef who knows their onions will tell you that you can reduce the repetition factor of garlic by slicing each clove lengthways and taking out the bitter green inner core, but this may be taking things too far.

Next, peel the potatoes and cut them into 1cm cubes. If you do not have the knife skills of Gordon Ramsay, this may take quite a while. It always does with me, but the uniformity of the cubelettes reduces their cooking time.

Now add the olive oil to a non-stick frying pan. The better the non-stick finish of the pan, the less likely your omelette will be to stick to the pan at the moment of truth. Heat the oil over a medium heat. Once the oil is hot, add the potatoes and the finely chopped onion. The idea is to gently poach the contents of the pan, so the oil should not be so hot that the spuds turn to chips and the onions get crisp. This is not something that we Brits are accustomed to doing, but this is a Spanish dish and so Spanish rules apply.

The potatoes should be soft in 12 to 14 minutes, but don’t be shy about checking every so often with a sharp knife or skewer.

As the potatoes and onions poach in the oil, you can beat the eggs. The big trick here is to add a good pinch of salt, before beating, and, if you fancy it, a similar pinch of freshly ground black pepper. The other big thing is that you should not beat the eggs for too long, neither should they be beaten too vigorously. 30 seconds of light agitation with a fork should be ample.

Next drain the potatoes and onions of the surplus oil in a colander. If you have been bold and used a good cupful of olive oil, you may wish to put some sort of a receptacle beneath the colander to collect the oil. However, this oil will now have quite a load of potato starch contained within it and is probably only any good for making your next tortilla.

Add the potatoes and onions to a bowl and add the beaten eggs. (Spanish people will tell you that must add the eggs to the mixture, but in truth it makes little difference which ingredient is introduced to which; as long as they are introduced and then stirred to make sure that they amalgamate into a gloopy mess.)

The frying pan (which careful readers will know has been momentarily neglected) can now be put back on the heat and allowed to warm up for a minute or two. There should be enough oil left on the surface of the pan to carry on with the cooking process without the addition of any further oil.

Now add the egg, potato and onion mixture back to the pan and reduce the heat a little. You can now go away and leave things for 10 minutes while you have a cup of tea, returning solely to run a spatula around the edge of the pan and push any rebel rivulets of egg back into the nicely rounded shape we all know and love.

After 10 minutes you will be ready for the moment of truth. The turning of the tortilla. Take a large serving plate: that is to say any plate with a diameter considerably bigger than that of the frying pan. It is a good idea to have wiped the surface of this plate with a kitchen towel dipped in olive oil to help prevent the, by now half-finished tortilla sticking to the plate. Put the plate over the pan and its contents and remove everything from the heat, preferably retreating to a place where an eggy disaster will have the least catastrophic effect upon the surroundings. If you are right handed, you will be holding the frying pan in your left hand. Turn the pan through 180 degrees, at this time you need to clamp both pan and plate together as firmly as possible; the whole lot will now be surprisingly heavy. This manoeuvre will mean that the plate is now bottom most and the pan – free now of any load – will be uppermost. The cooked surface of the tortilla will now be visible upon the plate. If things have gone to plan it will now have that brown, ever so slightly charred look that is one of the most appetising sights in the world of Spanish cuisine. The half cooked tortilla can now be slid – lubricated by the coating of oil on the plate- back into the waiting pan. Continue to cook for another ten minutes, lowering the heat if you feel nervous about your hard work sticking to the pan, and titivating the edges occasionally with your spatula.

After ten minutes your work is done. Slide the tortilla from the pan onto a serving plate. The best temperature at which to serve a tortilla is achieved by the simple expedient of leaving it for another 15 minutes or so to achieve that warm, but not really hot, temperature that is the mark of much Mediterranean cuisine. Serve with a green salad and that glass of wine you so richly deserve for producing this Spanish classic.