Making the Poolish:

1. In a large mixing bowl, whisk together the flour and yeast. Sir in the water using a wooden spoon or Danish dough whisk until the mixture is completely blended. Scrap the bowl down using a dough scraper or spatula. Cover with plastic wrap and let the poolish rest overnight at room temperature (70 – 75 degrees F.) for 8 to 12 hours.
   

Making the Final Dough:

1. The next morning, when the poolish is ripe, remove the plastic wrap and pour the water around the edges of the bowl to loosen it. Stir the mixture to completely break up the poolish.
2. In a separate bowl, whisk together the flours and yeast. Hold the salt. It will be added after the autolyse (step 4).
3. Add the flour mixture to the poolish mixture and mix thoroughly using a Danish dough whisk or wooden spoon. Continue mixing until the dough is too thick to mix with the whisk or spoon; then switch to using your hands. Wet your hands then mix the dough using the fold-and-turn method in the bowl.
4. When the dough is thoroughly incorporated, scrap the bowl down using a dough scraper or spatula. Then cover with plastic wrap and let the dough rest (autolyse) for 15 – 20 minutes.
5. Remove the plastic wrap and sprinkle the salt over the top of the dough. Thoroughly mix the salt into the dough using your fingers. Add a little bit of water if necessary.
6. Scrap the bowl down again, recover with plastic wrap (or a kitchen towel), and let the dough bulk ferment in the bowl for 2 – 2 1/2 hours. During the bulk fermentation, do a series of stretch and folds on the dough every 30 minutes for the first 1 1/2 hours for a total of 3 folds.
   
7. Lightly flour a work surface. Uncover the dough, and transfer it to the work surface. Pat it out into a rectangle and degas the dough slightly. Divide it into three equal rectangles by weight (273 grams). Preshape the rectangles into logs (refer to the video to learn the technique). Place the logs seam side down on a floured board or work surface. Cover with a kitchen towel or couche and let them bench rest for 30 minutes.
   
   
8. Uncover the dough and transfer the preshaped loaves to a clean work surface. Gently press on each piece to lightly degas it and shape into a baguette shape. Place each baguette seam-side up on a floured couche. Bring the folds of the couche up between the loaves. Cover the loaves with a towel and let them proof for 45 minutes.
   
9. While the loaves are in the final rise, preheat the oven to 475 degrees F. and place the baguette baker on the bottom shelf. Allow the oven and the baguette baker to preheat for at least 45 minutes.
10. Carefully remove the preheated baker from the oven using heavy oven mitts. Place the lid on a heavy towel or pot holder to keep it from cracking from the temperature change. Put the bottom of the baker on another towel or pot holder. Sprinkle the bottom of the baker with cornmeal.
11. Transfer the loaves from the couche to the baker using a wooden board or a bench knife. Score the loaves with 4 long slashes. You can score them before you transfer them to the baker if you prefer. The loaves expand when you slash them, so you might find it easier to transfer them first. Just be careful not to burn yourself on the hot baker.
12. Using heavy oven mitts, place the bottom of the baker in the oven and set the lid on top. Let the loaf bake for 15 -20 minutes with the lid on; then remove the lid and let it bake for another 10 minutes or until it is a deep brown and sounds hollow when thumped on the bottom.
13. Remove the baker from the oven and transfer the loaves to a wire rack to cool completely before slicing.