Add the bread flour (250g) and room temperature water (250g) to a medium container (at least 1-quart capacity). Stir with a fork until no dry flour remains.

Sprinkle the tiny amount of instant-yeast (0.2g) over the surface and stir until evenly distributed. The mixture will look like thick pancake batter.

Use plastic wrap with a small gap, or a lid set ajar. poolish needs some air exchange during fermentation.

Leave at cool room temperature (65-70°F / 18-21°C) for 12-16 hours. Ready when domed, covered with bubbles, and roughly doubled. Should smell yeasty and slightly sweet.

Add the fresh bread flour (250g) and cool water (125g) to your mixing bowl. Mix until no dry flour remains.

Cover and rest for 20-30 minutes. This autolyse hydrates the flour before adding the poolish.

It should be domed and bubbly. If collapsed significantly, it's past peak but still usable—flavor may be slightly more acidic.

Add the poolish to the autolysed dough along with the salt (10g) and instant-yeast (2g).

Mix on low speed for 2 minutes until incorporated. Increase to medium speed and mix for 6-8 minutes until smooth and passes a modified windowpane-test.

Combine using a pinching and folding motion for 4 minutes. Turn onto a clean surface and use slap-and-fold technique for 8-10 minutes until smooth and elastic.

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

Perform a set of stretch-and-fold: wet hands, stretch one side up and fold over center, rotate 90° and repeat for all four sides. Flip dough so folds are underneath.

Repeat the stretch and fold process. You'll notice the dough becoming stronger and holding its shape better.

Perform a third set of folds. The dough should now feel airy and hold together well.

After 2-2.5 hours total, dough should be 50-75% larger, slightly domed, and jiggly. When poked, indent fills back slowly.

Turn dough onto a lightly floured surface. It will spread somewhat due to extensibility.

Using a bench-scraper, divide into 3 equal pieces (approximately 280g each).

Gently pat each piece into a rough rectangle. Fold top third down, bottom third up, like a letter. Flip seam-side down.

Cover loosely with a towel. Rest for 20 minutes to relax the gluten before final shaping.

Let shaped baguettes proof until increased by about 50% and feel light and airy when you gently lift the couche.

Press gently with a floured finger. Indent should spring back slowly and mostly fill in. If it springs back immediately, proof longer. If indent stays, bake immediately.

Dust generously with flour (rice flour works well, or 50/50 bread flour and rice flour).

Flip dough seam-side up. Press into rectangle about 4" × 6". Fold top edge to center and seal. Fold again to meet bottom edge. Seal seam firmly with heel of hand.

Roll back and forth under palms, applying gentle pressure outward toward ends. Taper ends with slightly more pressure. Final length: 12-14 inches.

Place seam-side up on floured couche. Create pleats between each baguette to support the sides. Cover loosely.

Place baking stone on middle rack and empty metal pan on rack below. Preheat to 500°F (260°C) for at least 45 minutes.

Gently roll each baguette from couche onto parchment, seam-side down.

Using a lame held at 30-45° angle, make 3-5 overlapping slashes down the length. Each cut 3-4" long, overlapping by ¼ inch. Work quickly.

Slide baguettes onto hot stone. Pour 1 cup hot water into metal pan below and close door quickly. Bake 10 minutes at 500°F.

Remove steam pan carefully. Reduce to 475°F (245°C). Bake 12-15 minutes more until deep golden brown with internal temp of 205-210°F.

Place shaped baguettes in perforated baguette pan. Score as above.

Spray oven walls with water or use steam pan. Bake at 475°F (245°C) for 22-25 minutes until deep golden.