Stage 1

Ingredients (to make 2 loaves)

250g sourdough starter (167% hydration, i.e. fed with 150g flour and 250ml water)

320g unbleached strong white bread flour

130g rye flour

700ml water

Method

Using a mixer with a dough hook, combine the flours, water and starter until more or less smooth. Transfer to a larger bowl if the mixture comes above two-thirds, for it will rise a little bit. Cover and leave for several hours or overnight.

Stage 2

Ingredients

320g unbleached strong white bread flour

130g rye flour

2 tsp fine sea salt

50g black treacle

25g dark brown sugar

35g cocoa powder

2 tsp instant coffee granules

2 tbsp caraway seeds

1/2 tsp fennel seeds

50g apple cider vinegar

Method

Add all ingredients to the bowl of dough that has been resting overnight and beat using a mixer with a dough hook for about 5 minutes until more or less smooth and elastic. While the dough rests for 5–10 minutes, oil two rectangular bread tins, roughly 22 cm long by 11 cm wide and 6.5 cm high, then dust the inside generously with flour. Beat the dough again for another minute.

Divide the dough and fill each tin just over half, but no more than two-thirds, full. Depending on the room temperature and activity of the starter, the dough will need 3-5 hours to prove until increased in size by a third at least, or until it has risen just over the top of the tins.

Stage 3

When the dough is roughly in its last hour of rising, preheat the oven to 230 °C/450 °F/Gas 8. When the oven is up to temperature and you are satisfied the dough has risen sufficiently, place the tins on the middle shelf. Bake for 30 minutes before removing the bread from the tins and baking for a further 10-15 minutes upside-down. If the bread has formed a good hard crust it is ready. To make extra sure, tap the bottom, which should feel hollow. Transfer to a cooling rack and leave until completely cool before cutting.