San Francisco Sourdough

Preparation info

  • Difficulty


  • Makes


    round loaves

Appears in

Making Bread at Home

Making Bread at Home

By Tom Jaine

Published 2005

  • About

The pioneers who marched west in America, who followed the trail into the prairie vastness, or eagerly set forth to pan for gold in California or the Yukon, were hardly able to rely on bakers and grocery stores for an ounce or two of yeast. They took their own leavening: a smidgeon of dough kept back from the last baking which could be reactivated for the next. If it was stored deep inside a sack of flour, it was proof against frosts, heatwaves, even Indian attacks!

So it was that they were called ‘sourdoughs’, but it was only those who got as far as San Francisco who were to be able to make this very specific sourdough, which develops its tang from the particular bacilli that seem partial to the air in the Bay. Everyone’s air is different, so a true San Francisco sourdough may be impossible to repeat elsewhere, as the leaven will take on different microbes and wild yeasts, depending on the kitchen, bakery and climate.

If you have no leaven from previous baking, see To make a sourdough leaven.


The leaven

  • 60 ml/2 fl oz cold water
  • walnut of leaven from previous baking
  • 120 g/4 oz stoneground wholemeal flour
  • pinch of ground cumin

The Sponge

  • 350 ml/12 fl oz warm water
  • 15 g/½ oz fresh yeast
  • 425 g/15 oz unbleached white bread flour

The Dough

  • 300 g/10 oz unbleached white bread flour
  • 2 teaspoons salt
  • ½ teaspoon bicarbonate of soda


  1. To make the leaven, mix the water with the walnut of leaven. Add the wholemeal flour and cumin, and knead to a homogenous dough with your fingertips. Put it in a small bowl covered with clingfilm and leave to ripen in a warm place (24°C/75°F) for about 6-9 hours. It will at least double in size.
  2. To make the sponge, mix the leaven with the water and the yeast to a soup, then add the 425 g/15 oz flour gradually, beating all the while. Give it at least 500 beats with the hand to really stretch the gluten. Leave in a covered bowl to rise at 21°C/70°F for anything up to 12 hours, but at least 2 hours. The longer it is left, the sourer it should be.
  3. Mix the flour for the dough with the salt and bicarbonate of soda, then add it to the sponge. Mix to a dough, then turn out on to a floured work surface and knead very well for 10-15 minutes, until it clears.
  4. Divide in two and mould each piece into a ball. Place on a slightly warmed and greased large baking sheet, or two if your oven is not big enough to take a large baking sheet. Cover with oiled clingfilm and leave to rise in a warm place (26°C/80°F) for 1½ hours. They will spread and rise. Meanwhile, heat the oven to 230°C/450°F/gas 8.
  5. Slash the loaves with cuts radiating from the centre, dust with flour and bake for 25 minutes, spraying the oven with water twice in the first 4 minutes. Reduce the temperature to 200°C/400°F/gas 6 and bake for about another 15 minutes, until the loaves sound hollow when tapped on the bottom. If the loaves spread and touch when proved on a single baking sheet, you can easily break them apart and check more reliably that they are cooked by pressing a finger into the exposed crumb. If the indentation does not spring back, they need more cooking. Cool the cooked bread on wire racks.