# What You Need:
→ Sourdough Starter
01 - 3.5 oz active sourdough starter (100% hydration)
→ Dough
02 - 14 oz bread flour
03 - 10 fl oz lukewarm water
04 - 0.35 oz fine sea salt
05 - 0.7 fl oz extra-virgin olive oil
→ Topping
06 - 2 medium yellow onions, thinly sliced
07 - 1 tbsp olive oil
08 - 1 tsp flaky sea salt
09 - 1 tsp fresh rosemary leaves
10 - Freshly ground black pepper to taste
# How to Cook:
01 - In a large bowl, combine sourdough starter, bread flour, and lukewarm water until a shaggy dough forms. Cover and rest for 30 minutes to allow flour hydration.
02 - Add fine sea salt and extra-virgin olive oil to the dough. Mix thoroughly until fully incorporated.
03 - Perform 3-4 sets of stretch and fold techniques every 30 minutes over the next 2 hours to build gluten strength and texture.
04 - Cover the bowl and allow the dough to rise at room temperature for 6-8 hours until doubled in volume.
05 - Generously oil a 9x13-inch baking pan. Gently transfer dough to the pan without deflating. Using oiled fingers, stretch and press the dough evenly to fill the pan.
06 - Cover the pan and refrigerate overnight for 8-12 hours to develop flavor complexity and improve texture.
07 - Heat 1 tbsp olive oil in a skillet over medium-low heat. Add sliced onions and cook, stirring occasionally, for 20-25 minutes until deeply golden, soft, and sweet. Allow to cool completely before use.
08 - Remove dough from refrigerator and let rest at room temperature for approximately 1 hour before baking.
09 - Preheat oven to 425°F. Using fingertips, create dimples across the dough surface. Drizzle with additional olive oil, then distribute caramelized onions, flaky sea salt, rosemary, and black pepper evenly over the top.
10 - Bake for 25-30 minutes until deep golden brown with crispy edges.
11 - Remove from oven and allow to cool slightly before slicing and serving warm.
