Step 1

Prepare the poolish:

Step 2

Dissolve the yeast in water. Mix with the wheat flour until no dry spots remain. Cover and leave to ferment at room temperature for 4-5 hours. Then transfer the poolish to the fridge and leave to ferment overnight or up to 2 days.

Step 4

Prepare the sourdough:

Step 5

Dissolve the sourdough starter in water. Mix with the rye flour until no dry spots remain. Cover and leave to ferment at room temperature for 16-18 hours.

Step 7

Prepare the final dough and leave it to rise:

Step 8

In a bowl, combine the poolish, sourdough, and the rest of the ingredients for the final dough. Gently knead into a smooth dough for about 10-15 minutes or until you can stretch out the dough very thinly without it tearing. The dough temperature after kneading should ideally be around 22-25 °C (71-77 °F).

Step 10

Cover the dough and leave it to ferment at room temperature for 1.5 hours.

Step 12

Shape and proof the dough:

Step 13

Preheat your oven with baking steel or stone inside to 240 °C (465 °F). Place a tray filled with water on the bottom of the oven to generate steam.

Step 15

Transfer your risen dough onto a floured work surface. Shape into an oblong and leave to proof in a banneton, seam-side up, at room temperature until the dough is ready to be baked, about 30 minutes.

Step 17

Score and bake the bread:

Step 18

Invert the proofed dough onto a piece of parchment paper. Score the loaf lengthwise with a serrated bread knife and transfer it onto your pre-heated baking steel or stone.

Step 20

Bake the bread with steam for 10 minutes at 240 °C (465 °F). Then remove the water tray from the oven and turn down the heat to 210 °C (410 °F). Continue to bake the bread until browned to your liking, about 45 more minutes. Make sure to leave the loaf long enough in the oven so that it turns out crispy.

Step 22

Leave the baked loaf to cool down completely for a few hours before slicing it.