Ohhh this one is HEAVEN...
Rich, savory, aromatic, and cheesy — the kind of bread that makes your whole kitchen smell unbelievable.

This loaf is loaded with sweet, slow-caramelized onions and pockets of melty Gruyère. It’s perfect alongside soups, holiday dinners, charcuterie boards, or simply toasted with butter.

This one ALWAYS gets rave reviews — it’s classic, elegant, and completely irresistible.

🧂 Ingredients

Starter

  • 200 g active sourdough starter (fed and bubbly)

Main Dough

  • 450 g organic unbleached all-purpose flour
  • 50 g organic whole wheat flour
  • 310 g water (room temperature)
  • 9 g fine sea salt
  • 21 g honey or maple syrup (optional, balances the savory)

Mix-Ins

  • 2 medium yellow onions, thinly sliced
  • 1 tbsp butter + 1 tbsp olive oil (for caramelizing)
  • ½ tsp salt (for the onions)
  • 150–200 g Gruyère, grated or chopped into small cubes
  • Optional: ½ tsp black pepper or fresh thyme

🔥 Caramelize the Onions

  1. Heat butter and olive oil in a skillet over medium-low heat.
  2. Add sliced onions and ½ tsp salt.
  3. Cook slowly for 25–35 minutes, stirring occasionally, until deep golden and sweet.
  4. Let cool completely before adding to dough.

    Tip: Do NOT rush this step. Deep caramelization = big flavor.

👩‍🍳 Instructions

1. Mix & Autolyse

In a large bowl, whisk together starter, water, and honey.
Add flours and mix into a shaggy dough.
Cover and rest 30 minutes.

2. Add Salt & Build Strength

Sprinkle in the sea salt and fold the dough to incorporate.
Over the next 2 hours, perform 3–4 sets of stretch-and-folds every 30 minutes.
The dough will become smooth and elastic.

3. Add Onions & Gruyère

On your final fold:
Gently fold in the caramelized onions and Gruyère (reserve a handful of cheese for the top if you want a cheesy crust).
Distribute evenly but avoid tearing the dough.

4. Bulk Fermentation

Let the dough rise at room temp (70–75°F) until puffy and roughly doubled — about 4–6 hours depending on your starter.

5. Shape & Cold Proof

Turn dough onto a lightly floured surface, shape into a tight boule or batard, and place seam-side up in a floured banneton.
Cover and refrigerate overnight (8–12 hours).

6. Bake

Preheat oven to 475°F (245°C) with a Dutch oven inside for at least 45 minutes.
Turn dough onto parchment, score deeply, sprinkle on reserved Gruyère if desired, and transfer to hot pot.

Bake:

  • 25 minutes covered
  • 15–20 minutes uncovered until golden and cheesy and irresistible

7. Cool & Enjoy

Let cool at least 1 hour before slicing.
(If you cut too soon the cheese won’t be fully set.)

🍞 Baker’s Notes

  • Gruyère melts beautifully but stays slightly nutty and toasty — perfection in sourdough.
  • For even MORE flavor, add ½ tsp fresh thyme or black pepper to the onions while they cook.
  • Amazing for grilled cheese, patty melts, or French onion soup pairings.
DOWNLOAD the Recipe HERE

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