Add the bread flour and room temperature water to a medium bowl. Mix with a fork or your hand until no dry flour remains. The mixture will be shaggy and rough.

Sprinkle the salt and instant-yeast over the dough. Mix thoroughly until both are fully incorporated and the dough becomes smooth, about 2 minutes of working it with your hands.

Cover the bowl with plastic wrap or a damp towel. Let it sit at room temperature (70-75°F) for 1 hour. The dough will relax and just begin to show signs of activity.

Transfer to the refrigerator. Ferment for at least 12 hours and up to 24 hours. The dough will rise slowly, develop flavor compounds, and be ready to use cold.

Add the fresh bread flour (350g) and cool water (230g) to your mixing bowl.

Mix until no dry flour remains. The dough will be rough and shaggy.

Cover and let rest for 20-30 minutes.

Take out the pâte fermentée and tear it into 6-8 pieces.

Add the torn pieces to the autolysed dough along with the salt (7g) and instant-yeast (3g).

If using a stand mixer: Mix on low speed (speed 2) for 3 minutes to incorporate everything. Increase to medium speed (speed 4) and mix for 5-6 minutes until the dough is smooth, pulls away from the sides of the bowl, and passes the windowpane-test.

If mixing by hand: Squeeze and fold the dough in the bowl to incorporate the pâte fermentée, about 3-4 minutes. Turn onto your work surface and knead for 8-10 minutes until smooth and elastic.

Transfer the dough to a lightly oiled container or bowl. Cover with plastic wrap or a damp towel.

Let ferment at room temperature until the dough shows signs of activity.

Wet your hands. Reach under one side of the dough and stretch it up, then fold it over the center. Rotate the container 90 degrees and repeat. Do this for all four sides. Flip the dough over so the seams are underneath. Cover and continue fermenting.

Let ferment until the dough has increased in volume by about 75% (not quite doubled).

Flour your work surface lightly. Turn out the dough and divide it into two equal pieces using a bench-scraper. Each piece should be approximately 450g.

Working with one piece, gently gather the edges toward the center, creating a rough round. Flip it seam-side down.

Use your bench-scraper to drag the round toward you, creating surface tension on the outside.

Cover loosely with a towel or plastic. Let rest for 15-20 minutes (bench-rest). This relaxes the gluten and makes final shaping easier.

Lightly flour your work surface. Working with one piece at a time, flip the dough over so the seam side faces up.

Gently press the dough into a rough rectangle, about 6 inches wide and 8 inches long.

Fold the top third down toward the center. Press gently to seal.

Fold the bottom third up to meet the top edge. Press to seal.

Starting from the center, use the heels of your hands to seal the seam, rocking the dough back and forth slightly to create tension.

Roll the dough gently to even out the shape. It should be 8-10 inches long with tapered ends.

Place each shaped batard seam-side up in a floured banneton, or seam-side down on a floured couche or sheet of parchment. Cover loosely.

Place your Dutch oven in the oven and preheat to 475°F (245°C) for at least 45 minutes.

Gently turn the loaf out onto parchment paper. If it proofed in a banneton, flip it seam-side down.

Using a bread-lame or sharp razor blade, make one long slash down the center at a 30-45 degree angle, about ½ inch deep. Work quickly and confidently.

Carefully transfer the loaf (on its parchment) into the hot Dutch oven. Cover with the lid.

Bake covered for 20 minutes. The trapped steam does the work for you.

Remove the lid, reduce temperature to 450°F (230°C), and bake uncovered for 18-22 minutes more until deep golden brown.

Target internal temperature: 205-210°F (96-99°C). If you don't have a thermometer, the bread should sound hollow when tapped on the bottom.

Transfer to a wire cooling-rack. Let cool for at least 1 hour before slicing. The bread is still cooking internally during this time.

Place your baking stone on the middle rack. Put an empty metal pan on the rack below for steam. Preheat to 475°F (245°C) for at least 45 minutes.

Slide the loaves (on parchment) onto the hot stone.

Using a bread-lame, make one long slash down the center of each batard at a 30-45 degree angle, about ½ inch deep.

Immediately pour 1 cup of hot water into the empty metal pan below to create steam. Close the oven door quickly.

Bake with steam for 15 minutes.

Remove or vent the steam pan, reduce temperature to 450°F (230°C), and bake for 20-25 minutes more until deep golden brown.

Transfer to a cooling-rack. Let cool for at least 1 hour before slicing.