Add the remaining, except the raisins, to the refreshed starter, and knead well for 10 minutes.
Cover the bowl with a shower hat and let it rest for 2 hours on the counter.
Generously flour a medium sized (around 800 g) oval proofing basket.
Drain the raisins.
Remove the dough from the bowl and place it on a floury work surface. With wet hands, gently stretch it out into a flat rectangle that is just a little narrower than your basket. Scatter the raisins over the top of your dough and then gently press them into the dough so they stay put.
With the help of a scraper, fold the top edge the the middle and gently press along the seam. Fold the bottom edge to meet it and gently press along the seam. Still using the scraper, fold the dough in half, long wise and, with the heel of your hand, seal the long edge.
Sit the dough on sealed bottom seam and, using the sides of your hands, seal up both side edges.
Sprinkle flour over the dough and pick it up (it’s more robust than it seems) and put it seam side UP in the basket.
Cover it with a shower hat and let it rest for 3-5 hours. It won't pass a probe test (too much rye) but it will be visibly bigger, there may be little holes in the dough, and it will be very soft.
Preheat the oven to 230 degrees C, turn the dough out of the basket so that it is seam side DOWN on a baking tray lined with non stick baking parchment. Put it in the oven. Bake for 10 minutes and then reduce the heat to 200 degrees C and bake for a further 30 minutes.
Remove from the tin and let cool completely on a wire rack.