It’s a back to basics kind of bread, relying on natural yeast and bacterial cultures present in the flour and air, rather than the addition of bakers yeast (although a sneaky extra sprinkle can help things get going). The basic idea is that you initiate a kind of starter culture by mixing flour and water together and using it to catch and feed organisms that are all around in the air. It can take a few goes to get the ‘right’ culture but it’s pretty obvious by smell – ie if it's bubbly and smells yeasty and bready then it’s good, if it stinks then throw it away!
Once up and running the culture is kept alive by feeding with extra water and flour now and again, and it can be kept indefinitely (decades even!!) as a starter for breads, English muffins, waffles, pancakes etc. A quick google search revealed a few interesting websites on the subject, and comments by people who had been given their cultures by friends years and years ago, or been passed down through generations as kind of family heirlooms. Check out some info from S. John Ross for starters, also here's nice sourdough blog and of course wikipedia. There’s plenty of info in the RC Family Cookbook too.
What I did at RC was to mix 2.4L water with 2 kilos flour and a few ladelfulls of the starter culture. The resulting very wet paste was left overnight to form a ‘sponge’, to which 2 more kilos of flour were added the next morning, together with 2% salt. Knead for 10 mins, prove for 40, then bake. Easy! I’m going to have a go and making a starter culture from scratch but I really like the idea of an heirloom one. Anyone got a sneaky bit of starter culture that they’d like to share to begin a west end colony??
Here's a pic taken on the beach at Lyme Regis, a few mins down the hill from the campsite, and also the lovely view of RCHQ taken from the track that everyone walks down after leaving the cars at the top of the hill by the road. Nice.