For a small loaf (24cm bread tin):
400g sourdough
150ml lukewarm water
100g rye or wholemeal rye flour
300g white bread flour
1 tsp sea salt
1/2 demerara sugar

Mix the sourdough with the water, add the flour, the salt and sugar, leave for an hour. The dough should raise slightly. Mix it again and place in a bread tin ( oiled and sprinkled with bran, rye flakes or coriander seeds), brush the top with oil, cover with oiled film and leave for a few hours, or until doubled.
Sprinkle with poppy seeds and place in a cold oven. Set the tempereture to 200 C and bake for an hour. When the oven reaches 200 C, spray its walls and the bread with lukewarm water.
Cool on a wire rack.