01 - Combine bread flour and lukewarm water in a large bowl. Mix until just incorporated, cover, and let rest for 30-45 minutes to develop gluten structure.
02 - Add active sourdough starter and sea salt to the dough. Mix thoroughly until fully incorporated and smooth.
03 - Perform stretch-and-fold technique every 30 minutes for 2 hours, completing 4 sets total. Keep dough covered between folds to prevent drying.
04 - Let dough rest at room temperature for 1 hour after final fold to relax gluten.
05 - Turn dough onto lightly floured surface. Gently stretch into rectangle. Spread basil pesto evenly, leaving ¾-inch border. Sprinkle 1 oz Parmesan over pesto layer.
06 - Roll dough into tight log from short end. Shape into round or batard form, ensuring seam is sealed.
07 - Place dough in well-floured banneton or bowl, seam side up. Cover and proof at room temperature for 2-3 hours, or refrigerate overnight for enhanced flavor development.
08 - Preheat oven to 450°F with Dutch oven or baking stone inside for at least 30 minutes to ensure proper heat retention.
09 - Turn dough out onto parchment paper. Brush surface with olive oil and sprinkle remaining 0.8 oz Parmesan cheese. Score top as desired.
10 - Transfer to preheated Dutch oven and bake with lid on for 20 minutes to create steam and develop oven spring.
11 - Remove Dutch oven lid and continue baking for 18-20 minutes until golden brown with crispy crust. Internal temperature should reach 200°F.
12 - Cool completely on wire rack for at least 1 hour before slicing to preserve crumb structure.