In a bowl, mix the sourdough starter with 30 g of water until mostly dissolved.

Add in 60 g of wheat flour and mix until fully combined.

Leave it out overnight on the counter to rise and double in size.

Dissolve the active leaven in 310 g of lukewarm water.

Add 350 g of strong bread flour and mix until shaggy.

Cover and let it rest for 45 to 60 minutes.

Sprinkle 9 g of salt over the dough and mix it in.

Stretch and fold the dough gently for a few minutes until elastic.

Transfer dough to a lightly oiled proofing container.

Let it rise in a warm place (around 28 °C) for bulk fermentation, performing 6 sets of coil folds.

Perform the first three folds every 15 minutes, and the last three every 30 minutes. After the last fold, let the dough rise for an additional three hours.

Line a baking tray with parchment paper.

Turn out the dough on a floured surface and dust the top with flour.

Divide into six rectangular pieces and place on the baking tray.

Cover with a tea towel and allow to proof for 1 hour.

Preheat oven to 230° C 30 minutes before baking.

Bake the rolls for the first 10 minutes with steam.

Open the oven door briefly to vent steam, then finish baking for another 10 to 12 minutes until golden brown.

Let cool on a wire rack for at least 30 minutes before slicing.