The night before baking the bread, mix the rye flour with 450ml of warm water in a large bowl. Add the sourdough starter and stir well. Cover loosely with a plastic bag and leave to ferment overnight.

In the morning remove 75g of the ferment into a covered glass jar and place in the fridge until the next time a sourdough starter is needed.

To the remaining ferment, add the wholemeal flours, peeled bananas, linseeds, cinnamon, salt & walnuts. Knead in a stand mixer for ten minutes. The mixture is quite wet, so it’s a bit more difficult to do by hand, but not impossible.

Dust a proving basket with flour, then press the dough into it. Alternatively, form the dough into a freestyle loaf and place on a greased or lined baking tray. As the dough is quite a soft one, a free style loaf will flatten out. For a more uniform loaf, place the dough into a 1 kg/2lb loaf tin or two smaller tins.

Cover loosely with a plastic bag, ensuring it doesn’t touch the dough and leave to prove until the loaf has risen by about ⅓. This could be anything from 2 to 6 hours depending on the temperature of the room and the liveliness of the starter.

Turn the loaf out of the proving basket, if using, onto a greased baking tray. Otherwise, dust with a little spelt flour and slash the top 2-4 times with a sharp knife if liked.

When, or just before, you think the loaf is ready for baking, turn the oven on to 220℃ (425℉, Gas 7).

Place the bread in the oven and turn the temperature down to 200℃ (400℉, Gas 6). Bake for 40 minutes or until the bread sounds hollow when the base is tapped. Allow a further 10 minutes or so if baking in a tin. Place on a wire rack to cool.