### Instructions:
1. **Activate the Yeast:** In a large mixing bowl, combine the warm water, yeast, and sugar. Stir gently and let it sit for 5-10 minutes until foamy. This indicates the yeast is active.
2. **Add Discard and Flour:** To the foamy yeast mixture, add the sourdough discard and half of the all-purpose flour (250g). Mix well with a wooden spoon or Danish dough whisk until a shaggy dough forms.
3. **Add Remaining Flour and Salt:** Gradually add the remaining all-purpose flour (250g) and the fine sea salt. Mix until all the flour is incorporated and a cohesive dough forms.
4. **Knead the Dough:** Transfer the dough to a lightly floured surface. Knead for 8-10 minutes, or until the dough is smooth, elastic, and passes the windowpane test (you should be able to stretch a small piece of dough thin enough to see light through it without tearing).
5. **First Rise (Bulk Fermentation):** Lightly oil a clean bowl. Place the dough in the bowl, turning it once to coat with oil. Cover the bowl with plastic wrap or a clean kitchen towel and let it rise in a warm place for 1-1.5 hours, or until doubled in size.
6. **Shape the Loaves:** Gently turn the risen dough out onto a lightly floured surface. Divide the dough into two equal pieces. For each piece, gently stretch and pat it into a rough rectangle. Fold the top edge down to the middle, then the bottom edge up to the middle, sealing the seam. Roll the dough into a tight cylinder, sealing the seam along the bottom. Gently taper the ends to create the classic French loaf shape.
7. **Second Rise (Proofing):** Line a baking sheet with parchment paper or a floured couche. Carefully transfer the shaped loaves to the baking sheet or couche, leaving some space between them. Loosely cover with plastic wrap or a clean kitchen towel and let them proof for 30-45 minutes, or until noticeably puffy.
8. **Preheat Oven and Prepare for Baking:** While the loaves are proofing, preheat your oven to 450°F (232°C). Place a shallow oven-safe pan on the bottom rack of your oven (this will be used to create steam for a crispy crust).
9. **Score the Loaves:** Just before baking, use a very sharp knife or a bread lame to make 3-4 diagonal slashes across the top of each loaf.
10. **Bake with Steam:** Carefully transfer the baking sheet with the loaves to the preheated oven. Pour about a cup of hot water into the shallow pan on the bottom rack (be careful of the steam!). Quickly close the oven door.
11. **Bake:** Bake for 20-25 minutes, or until the loaves are deeply golden brown and sound hollow when tapped on the bottom.
12. **Cool:** Transfer the baked loaves to a wire rack to cool completely before slicing and serving.
### Short Tips:
* **Don’t over-knead:** While kneading is important, go by the feel of the dough – smooth and elastic.
* **Warmth is key for rising:** A slightly warm spot (like near a sunny window or in a slightly warm, off oven) will help your dough rise beautifully.
* **Embrace the steam:** The steam at the beginning of baking is crucial for a crisp, beautiful crust.
* **Discard flexibility:** This recipe is forgiving. Your sourdough discard can be from a recent feeding or have been sitting in the fridge for a few days.
* **Enjoy fresh:** French bread is best enjoyed on the day it’s baked, but leftovers can be refreshed by toasting.
