Quick Recipe Version (TL;DR)
Quick Ingredients
- 3 large yellow onions (about 2 lb / 900 g), thinly sliced
- 2 tbsp unsalted butter + 1 tbsp olive oil
- 2 tbsp dry white wine or dry sherry, 1 tsp vinegar (optional)
- 500 g bread flour (about 4 cups + 2 tbsp)
- 325 g warm water, 95–100°F (about 1 1/3 cups)
- 2 tbsp olive oil
- 7 g instant yeast (2 1/4 tsp)
- 10 g kosher salt (1 3/4 tsp), 1 tsp sugar, 1/2 tsp black pepper
- 250 g Gruyère (9 oz): 200 g in 1/2-inch cubes, 50 g grated
- 1 egg (for wash), fresh thyme, flaky salt (optional)
Do This
- 1. Caramelize onions low and slow in butter/oil with salt, 45–60 minutes; deglaze with wine; cool and chop. Reserve 1/3 cup for topping.
- 2. Mix flour, yeast, salt, sugar, and pepper; add warm water and olive oil. Knead until smooth and slightly tacky, 8–10 minutes.
- 3. First rise: cover and let double, about 60–75 minutes at room temp.
- 4. Pat dough to a 12×16-inch rectangle; spread onions (not the reserved portion) and scatter cheese cubes; fold letter-style and shape into a tight log.
- 5. Place in a greased 9×5-inch loaf pan; proof 35–45 minutes until 1 inch above rim. Preheat oven to 375°F (190°C).
- 6. Brush with egg wash; top with reserved onions, grated Gruyère, thyme, and flaky salt. Bake 35–40 minutes to 200–205°F internal; cool 45 minutes before slicing.
Why You’ll Love This Recipe
- All the cozy flavor of French onion soup baked into a sliceable, shareable loaf.
- Melty Gruyère pockets and jammy onions give you flavor in every bite.
- Approachable method: simple straight dough, classic loaf pan, no fancy equipment.
- Make-ahead friendly: caramelize onions in advance and bake when you want.
Grocery List
- Produce: 3 large yellow onions, fresh thyme
- Dairy: Gruyère cheese (9 oz), unsalted butter, 1 egg
- Pantry: Bread flour, olive oil, kosher salt, black pepper, sugar, instant yeast, dry white wine or dry sherry, vinegar (optional), flaky salt (optional)
Full Ingredients
Caramelized Onions
- 3 large yellow onions (about 2 lb / 900 g), halved root-to-stem, thinly sliced
- 2 tbsp unsalted butter
- 1 tbsp olive oil
- 1/2 tsp kosher salt
- 2 tbsp dry white wine or dry sherry (for deglazing)
- 1 tsp sherry or red wine vinegar (optional, for brightness)
- 1/2 tsp sugar (optional, only if onions are not naturally sweet)
- Freshly ground black pepper, to taste
Dough
- 500 g bread flour (about 4 cups + 2 tbsp)
- 325 g warm water, 95–100°F (about 1 1/3 cups)
- 7 g instant yeast (2 1/4 tsp; 1 packet)
- 10 g kosher salt (1 3/4 tsp)
- 1 tsp sugar
- 2 tbsp olive oil
- 1/2 tsp freshly ground black pepper
Filling & Topping
- 200 g Gruyère, cut into 1/2-inch cubes (about 7 oz)
- 50 g Gruyère, grated (about 1 3/4 oz) for topping
- 1 tsp fresh thyme leaves, plus extra for garnish
- 1 egg beaten with 1 tsp water (egg wash)
- Flaky salt, for finishing (optional)
Step-by-Step Instructions
Step 1: Caramelize the onions slowly
In a large, heavy skillet over medium-low heat, melt the butter with the olive oil. Add the sliced onions and 1/2 tsp salt. Cook, stirring every few minutes, until the onions go from translucent to deep golden brown and jammy, 45–60 minutes. If fond builds up on the pan, deglaze with 1–2 tablespoons water as needed. When the onions are a rich mahogany color, stir in the wine (or sherry) and cook until the liquid evaporates, 1–2 minutes. Add the vinegar (optional) and a few grinds of pepper. Spread onions on a plate to cool completely, then roughly chop. Reserve 1/3 cup for topping; the rest is for the filling.
Step 2: Make the dough
In a large bowl (or the bowl of a stand mixer), whisk together the flour, instant yeast, salt, sugar, and black pepper. Add the warm water and olive oil. Mix until a shaggy dough forms, then knead until smooth, elastic, and slightly tacky—8–10 minutes by hand or 6–7 minutes on medium speed. If the dough is sticky, dust in just 1–2 teaspoons more flour; avoid over-flouring.
Step 3: First rise
Form the dough into a ball and place in a lightly oiled bowl, turning to coat. Cover and let rise in a warm spot until doubled, about 60–75 minutes at 72–75°F. Meanwhile, cut 200 g Gruyère into 1/2-inch cubes and finely grate 50 g for topping. Grease a 9×5-inch loaf pan and set aside.
Step 4: Laminate in onions and cheese
Turn the dough onto a lightly floured surface and gently pat to a 12×16-inch rectangle. Spread the chopped caramelized onions evenly over the surface, leaving a 1-inch border on all sides (remember to save 1/3 cup for topping). Scatter the Gruyère cubes and 1 tsp thyme over the onions. Fold the rectangle in thirds like a letter (short side over center, then other short side on top). Rotate 90 degrees, gently pat into a shorter rectangle, then roll into a tight log, pinching the seam closed. Tuck the ends under.
Step 5: Pan and proof
Place the log seam-side down in the prepared 9×5-inch pan. Cover and proof until the dough crowns about 1 inch above the pan rim and springs back slowly when poked, 35–45 minutes. About 15 minutes before baking, preheat the oven to 375°F (190°C). For convection, bake at 350°F (175°C).
Step 6: Top and bake
Brush the top gently with egg wash. Sprinkle the reserved caramelized onions and the grated Gruyère over the surface, pressing lightly so they adhere. Add a pinch of thyme and flaky salt if using. Bake on the center rack until deeply golden and the internal temperature reads 200–205°F (93–96°C), 35–40 minutes. If the top is browning too quickly, tent with foil for the last 10–15 minutes.
Step 7: Cool and slice
Cool in the pan for 10 minutes, then turn the loaf out onto a rack. For the best texture and cheesy pockets, let cool at least 45 minutes before slicing with a serrated knife. Serve warm, plain or with a swipe of softened butter.
Pro Tips
- Dry is key: fully caramelize and cool the onions so they do not waterlog the dough.
- Keep cheese in cubes for melty pockets; chill it while the dough rises so it stays firm during shaping.
- Weigh ingredients if possible—500 g flour and 325 g water land you right around 65% hydration for a tender crumb.
- Internal temperature tells the truth: pull the loaf at 200–205°F for a set crumb without gumminess.
- If you love a crisper crust, remove the loaf from the pan and bake directly on the rack for 5 extra minutes.
Variations
- Sourdough version: replace yeast with 120 g ripe 100% hydration starter, reduce water to 290 g, and bulk rise until doubled (2.5–4 hours). Proof as directed.
- Comté or Emmental swap: use the same amounts for a slightly nuttier or milder profile.
- Mushroom–onion: sauté 6 oz finely chopped cremini with the onions for an earthy twist; be sure to cook off moisture fully.
Storage & Make-Ahead
Caramelized onions can be refrigerated up to 5 days or frozen for 1 month. The shaped loaf can be covered and refrigerated overnight; bake straight from cold, adding 5–8 minutes as needed. Store baked bread, well wrapped, at room temperature for up to 3 days. For longer storage, slice and freeze up to 2 months; reheat slices in a 350°F (175°C) oven for 8–10 minutes or toast directly from frozen.
Nutrition (per serving)
Approximate for 1 of 12 slices: 290 calories; 12 g fat; 32 g carbohydrates; 12 g protein; 2 g fiber; 550 mg sodium.
