Sourdough Focaccia with Caramelized Onions
Tina BevkThis sourdough focaccia with caramelized onions is a combination of airy, chewy bread and the rich sweetness of caramelized onions. It’s perfect as a side dish, snack, or (my favorite!) a base for sandwiches. The sourdough gives it a subtle tang and unique structure, while the caramelized onions provide a deep, savory-sweet topping.
Best of all, it’s a simple recipe that comes together with just a little patience, making it a favorite in my kitchen for its simplicity and great flavor.
Sourdough Focaccia with Caramelized Onions
Ingredients
Sourdough Focaccia Ingredients:
- 2 ½ cups cups of all purpose flour
- 1 ⅓ cups cups of water
- 1/4 cups sourdough starter active
- 6 tbsp semolina flour
- 1 tbsp olive oil
- 1 tbsp salt
Caramelized Onions Ingredients:
- 1 ½ onions or more
- 1 ½ tbsp sugar
- 3 tbsp oil
Instructions
- The day before in the evening: Whisk together about 1/4 cup of sourdough with a bit of water in a medium-large bowl adding all the remaining water. Pour all purpose flour, semolina flour, salt and oil and mix together with a spoon as the dough will be quite sticky. Cover and let it double rise for the night at room temperature.
- Next day, in the morning or midday, with the help of a spatula, create a sticky ball and transfer it on a parchment paper on a baking tray or simply on a non-stick baking sheet. Spread the dough with oiled fingers.
- Let it raise for 1-2 hours (optional: cover with plastic wrap or towel so it doesn’t dry)
- For caramelized onions, first heat the pan on medium high heat until the oil is shimmering. Add the sugar and let it melt for 5-7 minutes.
- Then put the sliced onions in the oiled pan and cook them, always on a medium high heat, for at least 10-15 minutes until they become soft and of caramel color stirring every few minutes. Let it cool before topping the focaccia bread.
- After waiting 1-2 hours for the focaccia dough to rise, top it with caramelized onions and with oiled fingertips gently dimple the dough.
- Bake in the preheated oven at 392.0°F/200°C on the center-lower rack for 30 minutes or until golden brown.
- When ready, take out from the oven, drizzle olive oil on top and let it rest for 5-10 minutes before cutting and eating.
Notes
Nutrition
Ingredients
For the Dough:
- All-purpose flour – The foundation for a light and airy focaccia.
- Water – Hydrates the dough and keeps it moist during fermentation.
- Sourdough starter – Ferments and rises the focaccia.
- Semolina flour – Gives it a signiture texture and creates a slightly crisp bottom crust.
- Olive oil – Adds richness and helps create the characteristic focaccia crust.
- Salt – Enhances flavor and strengthens gluten structure.
For the Caramelized Onions:
- Onions – The only topping you need here, bringing sweetness and depth.
- Sugar – Speeds up the caramelization process.
- Oil – Keeps the onions from sticking and adds flavor.
See recipe card for quantities.
How to Make Sourdough Focaccia with Caramelized Onions
The day before in the evening: Whisk together about 1/4 cup of sourdough with a bit of water in a medium-large bowl adding all the remaining water. Pour all purpose flour, semolina flour, salt and oil and mix together with a spoon as the dough will be quite sticky. Cover and let it double rise for the night at room temperature.
Next day, in the morning or midday, with the help of a spatula, create a sticky ball and transfer it on a parchment paper on a baking tray or simply on a non-stick baking sheet. Spread the dough with oiled fingers.
Let it raise for 1-2 hours (optional: cover with plastic wrap or towel so it doesn’t dry)
Next step: make the caramelized onions.
For caramelized onions, first heat the pan on medium high heat until the oil is shimmering. Add the sugar and let it melt for 5-7 minutes.
Then put the sliced onions in the oiled pan and cook them, always on a medium high heat, for at least 10-15 minutes until they become soft and of caramel color stirring every few minutes. Let it cool before topping the focaccia bread.
After waiting 1-2 hours for the focaccia dough to rise, top it with caramelized onions and with oiled fingertips gently dimple the dough.
Bake in the preheated oven at 392.0°F/200°C on the center-lower rack for 30 minutes or until golden brown.
When ready, take out from the oven, drizzle olive oil on top and let it rest for 5-10 minutes before cutting and eating.
Hint: if it’s summer, let the dough rise overnight in a cool spot. During winter, you can start the dough in the morning and bake it in the evening to account for the slower rise in colder temperatures.
Baking Schedule
Same-Day Option
7:00 AM: Mix the dough and let it rise for 5–6 hours at room temperature.
12:30 PM: Shape the dough on a baking tray and let it rise for another 1–2 hours.
2:00 PM: Preheat the oven and caramelize the onions.
2:30 PM: Dimple, top with caramelized onions, and bake. Serve fresh in the afternoon.
Overnight Option
7:00 PM (Evening Before): Mix the dough and let it rise overnight for 8–10 hours.
7:00 AM (Morning): Shape the dough on a baking tray and refrigerate for a cold proof.
4:00 PM (Afternoon): Remove from the fridge and let the dough warm up for 1–2 hours. Preheat the oven and caramelize the onions.
6:00 PM: Dimple, top with caramelized onions, and bake. Enjoy for dinner!
Substitutions & Variations
- Toppings: Swap caramelized onions for cherry tomatoes, olives, or roasted garlic for a different flavor profile.
- Herbs: Sprinkle fresh rosemary or thyme over the dough before baking.
- Flour: Use bread flour instead of all-purpose for a chewier texture, but I’m warning you – it won’t be as soft at the same time!
💭Crucial Success Tips
For the best results, keep the dough temperature below 78.8°F (26°C) during fermentation. This prevents the dough from becoming overly acidic.
FAQ
Yes, you can replace it with additional all-purpose flour, but semolina adds a unique crispiness to the base.
Ensure your starter is active and your kitchen temperature is warm enough (above 68°F/20°C). If it’s too cold, let the dough rise longer.
Yes, you can use 1 tsp of dry yeast instead, but you’ll miss the tangy flavor that sourdough provides.
How To Store Sourdough Focaccia with Caramelized Onions
Room Temperature: Store leftovers in an airtight container for up to 2 days. Reheat in the oven for a fresh-baked taste.
Freezing: Slice and freeze for up to a month. Reheat slices directly in the oven.
Author: Tina Bevk
Tina, from the blog “Stretch and Folds,” balances motherhood and a passion for sourdough baking. Based in Slovenia, she offers practical sourdough tips and recipes, bridging European and American baking styles. Her blog simplifies sourdough for busy families, focusing on easy, nutritious sourdough recipes.
