A sourdough loaf is very different from what mostly passes as bread these days. In fact, it is the antithesis of the industrial factory loaf – that soft, structureless, flavour-lite bread that is produced in such huge quantities in this country. Sustain, whose Real Bread Maker Week starts today, reckons that well in excess of 90% of our bread is mass-produced either by the big brands or supermarkets. Sourdough, by contrast, is bread with immense character, with presence – bread with a point. And that's why I think you might want to have a go at making it yourself.

Of course, you can buy great sourdough, but if you've done so, you'll know it isn't cheap. A magnificent 2kg Poilâne loaf, for instance, will set you back about £10, while even smaller, less prestigious examples cost considerably more than standard bread. I'm not knocking that: the price reflects the quality of the ingredients and time that goes into making the loaf, something you'll appreciate if you make it yourself. But making sourdough at home is not expensive at all and, while it demands patience, it requires little actual effort. It might be a good 10 days from beginning your sourdough starter to the point when you can enjoy the first mouthful of a finished loaf, but there's very little work to be done in that time.

This starter, with which the whole process begins, is just a flour-and-water batter. Well, perhaps not "just". Because it will also contain, invisibly but crucially, the spores of wild, airborne yeasts – the ones that happen to be native to your own kitchen. These will begin to feed and multiply and, as they do so, all sorts of interesting things are produced: bubbles of gas, flavoursome alcohol and the acids that give sourdough its characteristic, slightly tangy taste. Within a week or so, the starter is ready to be used in a loaf – you take some of it, mix it with fresh flour and turn it into bread. The remaining starter, provided you "feed" it regularly, can then be kept indefinitely, ready to give you a loaf whenever you feel like it.

And you will feel like it. Because it isn't just sourdough's superb flavour that will reward your patience; its texture will, too. This bread has an elastic, ever-so-slightly-rubbery-but-in-a-really-good-way crumb and a proper, crisp, crunchy, robust crust. Freshly baked and smeared with cold, creamy butter, it's exceptional. Torn up, dabbed in good olive oil, and sprinkled with a few flakes of salt, it's a delight. It also has longevity. Over the days subsequent to baking, you'll find it makes the best toast ever, it's brilliant for bruschetta and, as it gracefully comes to the end of its life, it produces the very finest breadcrumbs and croutons.

If you make it, and like it, it pays to get into the rhythm of baking it regularly enough to make it your mainstay loaf. Sourdough-production – the nurturing of the starter, the mixing of the dough, the long, slow rise and the final, glorious bake – is one of those kitchen routines that's somehow life-affirming and transformative. And why wouldn't it be? You are, after all, growing your own bread.

Sourdough starter

Hugh Fearnley-Whittingstall's sourdough starter recipe: 'Make it with wholegrain flour and keep it warm in your kitchen, and you should see signs of life within 24 hours.' Photograph: Colin Campbell for the Guardian

The time it takes a starter to begin fermenting can be a few hours or a few days. But make it with wholegrain flour and keep it warm in your kitchen, and you should see signs of life within 24 hours.

About 100g strong bread flour (at least 50% wholegrain, such as wholemeal, spelt or wholegrain rye)

Up to 1kg bread flour (or a mixture of flours), to 'feed' the starter

In a large bowl, mix the flour with enough lukewarm water to make a batter the consistency of thick paint. Beat it well, then cover with a lid or clingfilm and leave somewhere fairly warm. A warm kitchen is fine, as is a coolish airing cupboard. Check it every few hours, until you can see fermentation has begun. This is signalled by the appearance of bubbles and a smell of, well, fermentation (it can smell quite unpleasant and acrid at this stage, but don't worry, it will mellow).

Your starter now needs regular feeding. Begin by whisking in 100g or so of fresh flour and enough water to retain that thick batter consistency – you can now switch to using cool water and to keeping the starter at normal room temperature. Leave it again, then, 24 hours or so later, scoop out and discard half the starter and stir in another 100g of flour and some more water. Repeat this discard-and-feed routine every day, maintaining the sloppy consistency and keeping your starter at room temperature, and after seven to 10 days you should have something that smells good: sweet, fruity, yeasty, almost boozy. Don't be tempted to bake a loaf until it's been on the go for at least a week.

If you're going to bake bread every day or two, maintain your starter in this way, keeping it at room temperature, feeding it daily, and taking some of it out whenever you need to. However, if you want to keep it for longer between bakings, add enough flour to turn it into a stiff dough, then it won't need another feed for four or so days. You'll just need to add more water when you come to make the "sponge" (see below). Alternatively, lull your starter into dormancy by cooling it down – it will keep for a week in the fridge without needing to be fed. You'll then need to bring it back to room temperature and probably give it a fresh feed to get it bubbling and active again. Combine these two approaches – keep your starter as a stiff dough in the fridge – and you can leave it for two weeks before it will need your attention again. If you know you won't be baking for a while, you can even freeze the starter; it will reactivate on thawing.

Sourdough loaf

For the sponge

About 150ml active starter (see recipe above)

250g strong flour (white, wholemeal or a mixture of the two)

For the loaf

300g strong bread flour (white, wholemeal or a mixture), plus more for dusting

1 tbsp rapeseed or olive oil

10g fine sea salt

The night before you want to bake your loaf, create a sponge: in a large bowl, combine 150ml of active starter with 250g flour and 275ml warm water. Mix, cover with clingfilm and leave overnight. In the morning it should be clearly fermenting: thick, sticky and bubbly.

To make the dough, add the 300g of flour to the sponge, along with the oil and salt, and incorporate. You should now have a fairly sticky dough. If it seems tight and firm, add a dash more warm water; if it's unmanageably loose, add more flour, but do leave it fairly wet – you'll get better bread that way.

Turn out the dough on to a lightly floured surface and knead until smooth and silky – about 10 minutes – then put in a lightly oiled bowl and turn it to coat with the oil. Cover with clingfilm and leave to rise. Sourdough rises slowly and sedately, so it'll take a few hours in a warm kitchen, and a few more in a cool larder. One good option is to knead it in the morning, then simply leave it all day – perhaps while you're at work – in a cool, draught-free place until it has more or less doubled in size and feels springy if you push your finger gently into it; alternatively, knead it in the evening and leave to rise overnight.

Deflate the risen dough by punching it down with your knuckles on a lightly floured surface. You now need to prove the dough (give it a second rising). First form it into a neat round, tucking the edges of the dough underneath itself so you have a smooth, round top and a rougher base.

If you have a proper proving basket, dust it liberally with flour. Alternatively, rig up a proving basket by lining a wide, shallow bowl with a clean, floured cloth. Place your round of dough smooth side down in the basket or bowl, cover with oiled clingfilm or a clean plastic bag, and leave to rise, in a warm place this time, for an hour and a half to three hours, until roughly doubled in size again. It's now ready to bake.

Heat the oven to its highest setting (250C/500F/gas mark 10 is ideal). If possible, have ready a clean spray bottle full of water – you'll be using this to create a steamy atmosphere in the oven, which helps the bread rise and develop a good crust. (You can achieve the same effect with a roasting tin of boiling water placed on the bottom of the oven just before you put the loaf in.)

Five minutes before you want to put the loaf in, place a baking sheet in the oven to heat up. Take the hot baking sheet from the oven, dust it with flour and carefully tip the risen dough out of the basket/bowl on to it; it will now be the right way up. If you like, slash the top of the loaf a few times with a sharp serrated knife (or snip it with a pair of scissors) to give a pattern. Put the loaf in the oven, give it a few squirts from the spray bottle and leave to bake for 15 minutes. Lower the heat to 200C/390F/gas mark 6, give the oven another spray, and bake for a further 25-30 minutes, until the now well-browned loaf vibrates and sounds hollow when you tap its base.

Leave to cool for at least 20 minutes – it's OK to slice it warm, but not piping hot.

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