500g whole-grain rye flour 500g strong white bread flour 700g water 10g salt 30g oil 40g sugar - e.g. molasses, malt, honey, treacle 50g rye sourdough starter Over 24 to 48 hours, mix, stretch and fold until it's very elastic. Shape, rise and cook - two loaves - 30 minutes in a hot oven. Be prepared to shape and cook early if/when the dough becomes active.