01 -
Mix the mature sourdough starter, sugar, water, and bread flour until a shaggy dough forms. Cover and rest in a warm area for 1 hour.
02 -
Add salt and olive oil to the dough. Use your fingers to press and fold the dough repeatedly until these are fully incorporated.
03 -
Transfer dough to a covered container and let rise in a warm spot for 1.5 hours. Every 30 minutes, perform stretch and folds to develop structure, aiming for a square shape.
04 -
Place the dough on a well-oiled baking sheet or parchment-lined pan. Let it rest at room temperature for 3 to 4 hours until bubbly and naturally spread. If using two 10-inch cake pans, divide dough in half accordingly.
05 -
Optionally, cover dough loosely with oiled plastic wrap and refrigerate overnight or up to 3 days. Bake directly from cold when ready.
06 -
Preheat oven to 450°F (232°C) and place a baking stone or steel in the center if available.
07 -
Dimple the dough heavily by pressing fingers deep into the surface. Drizzle olive oil, sprinkle salt, and add rosemary or preferred toppings.
08 -
Bake the focaccia on the preheated stone or steel for approximately 20 minutes until golden on top and crispy on the bottom.
09 -
Remove from oven and immediately drizzle additional olive oil over the hot focaccia before serving.