Sourdough. (Very long, sorry.)
A previous poster asked for my sourdough recipe. I've only just started doing this but it has been working a treat. Here is how I do it:
If you haven't got a live sourdough starter you need to make one. It's very easy. You can use wheat or rye flour, or spelt I think, but stick to just one type of flour for your starter. I suggest organic whole grain flour for this (only for the starter) as you want to get a healthy mix of yeasts and bacteria going.
In a large bowl (really, it has to be quite large) add about 100g of flour and 100 ml of lukewarm water. Mix thoroughly. You are looking for a thick pancake/waffle batter consistency, so adjust flour and water if needed. Set aside in a warm place. After a while, cover with cling film and leave aside in the warm place (between 20 and 26 degrees or so).
12 hours later thoroughly beat your batter with a spoon. Then cover with cling film and set aside again in a warm place. 12 hours later add another 100g of flour and 100ml of lukewarm water (circa) to your mix, combine, and beat thoroughly with a spoon. Aim to have a waffle batter consistency again. Cover and set aside.
Repeat this pattern for about four days. You don't need to do anything else. You should end up with an airy dough/batter, bubbling, with a slightly acidic smell. Don't worry if it smells funny during the earlier stages. Once the yeasts and bacteria have stabilised the smell should be distinctive but in no way bad/off.
You may end up with over 1kg of sourdough. You probably only need less than half that for the first loaf.
My own sourdough is made from rye flour but I use strong white flour for the actual loaf.
For a mild to medium soured loaf, use 300g of sourdough, 600g of strong white flour, 1 tbsp salt and ca. 250-300ml of lukewarm water. Knead dough well to stretch the gluten. Form a loaf (use a proving basket if you have) and set aside to prove. (Oven set to 50 degrees works well.) This could take up to three hours or so with a new sourdough starter. You want it to double in size. Keep the top of your loaf moist by spraying it with water every now and then.
Once proved remove dough from oven and preheat oven to 230 degrees. Bake the loaf at that temperature for 15 minutes. Turn the temperature down to 180 degrees and bake for another 45 minutes or so.
Your remaining sourdough will keep in the fridge for a couple of months if you turn it into very dry crumbs (using the same flour). Add at least its weight again in flour and crumble away. Put in a clean, dry, air tight container and store in the fridge. When you are ready to bake again simply add water.
Always remember to keep at least 50g of your sourdough back as a starter for next time.