Sourdough Onion Focaccia Bread (Printable Version)

A chewy focaccia topped with golden caramelized onions and a touch of sea salt.

# What You'll Need:

→ Sourdough Starter

01 - 3.5 oz active sourdough starter (100% hydration)

→ Dough

02 - 14.1 oz bread flour
03 - 10.1 fl oz lukewarm water
04 - 0.35 oz fine sea salt
05 - 0.68 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, optional
10 - Freshly ground black pepper, optional

# Directions:

01 - In a large bowl, combine sourdough starter, bread flour, and water until a shaggy dough forms. Cover and rest for 30 minutes.
02 - Add salt and 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.
04 - Cover the bowl and allow dough to rise at room temperature for 6-8 hours until doubled in size.
05 - Generously oil a 9x13 inch baking pan. Gently transfer dough to the pan without deflating. Using oiled fingers, stretch and press the dough to fill the pan evenly.
06 - Cover the pan and refrigerate for 8-12 hours overnight to develop flavor and 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 golden, soft, and sweet. Allow to cool completely.
08 - Remove dough from refrigerator and let sit at room temperature for approximately 1 hour.
09 - Preheat oven to 425°F (220°C). Using your fingertips, create dimples across the dough surface. Drizzle with additional olive oil.
10 - Evenly distribute caramelized onions, sea salt, rosemary, and black pepper across the dough. Bake for 25-30 minutes until golden brown with crisp edges.
11 - Cool briefly before slicing and serving warm.

# Expert Advice:

01 -
  • The overnight cold rise develops this incredible depth of flavor that you simply can't rush, plus it fits perfectly into a lazy weekend schedule.
  • Those caramelized onions are absolute magic—sweet, soft, and they make the bread taste like it came from somewhere fancy.
  • It's genuinely foolproof once you understand the rhythm of stretch and folds; even if you're not a sourdough expert yet, this will work.
02 -
  • Don't skip the overnight refrigeration—it's not just for convenience; it's where the flavor develops and the gluten relaxes into something truly special.
  • The stretch and folds are your best friend if you don't have a stand mixer; they build gluten strength without aggressive kneading and you'll actually feel the dough transform under your hands.
  • Caramelize those onions low and slow over medium-low heat; high heat will brown them fast but won't give you that sweet, jammy texture you're after.
03 -
  • If your dough seems too sticky during the transfer, chill it for 15 minutes before stretching it into the pan—cold dough is much more cooperative.
  • The dimpling step isn't just for looks; those little pockets catch oil and get extra crispy, creating texture contrast that makes each bite interesting.
  • Taste your caramelized onions as they cook; they should taste sweet and jammy, almost like onion marmalade, because that sweetness against the savory bread is where the magic lives.
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