Caramelized Onion Sourdough Bread with Jarlsberg

A crusty caramelized onion sourdough loaf folded with nutty Jarlsberg — naturally leavened with sifted landhvete and emmer.

Print Recipe Pin Recipe

Prep Time 1 15

Cook Time 35

Fermenting & proofing 20

Total Time 21 50

Servings: 2 loaves

Course: Bread, Side Dish

Cuisine: Nordic, Scandinavian

Ingredients Equipment Method Notes

Ingredients

Browned onions (make first — they must be cold)

3 large yellow onions about 720 g / 1.6 lb, thinly sliced
3 tbsp neutral oil enough to coat the pan

Dough

140 g active sourdough starter about ⅔ cup — bubbly, ripe and passing the float test
400 g water about 1⅔ cups, lukewarm
350 g sifted landhvete flour about 2¾ cups plus 2 tbsp — or bread flour
250 g sifted emmer flour about 2 cups — or sifted spelt
15 g fine sea salt about 2½ tsp

Folded in

240 g Jarlsberg about 1¾ cups, cut in ¼ in / ½ cm dice
the cooled browned onions roughly 230 g / 1 cup once reduced

For the baskets

25 g rice flour for dusting the linen cloths; it doesn't absorb, so the loaves release cleanly

Equipment

Digital kitchen scale This dough runs on weight, not volume — 67% hydration leaves no room for guessing.
Heavy skillet or cast iron pan You need a wide, heavy base to brown 1.6 lb of onion without steaming it.
2 Banneton proofing baskets, 8 in Hold the shape through the cold retard and leave the spiral pattern. Dust with rice flour. If you only have one, proof the second loaf in a cloth-lined bowl.
2 Linen proofing cloths Line the bannetons — rice flour plus linen is the combination that releases cleanly with heavy inclusions.
Bench scraper Essential here. A dough loaded with cheese and onion sticks, and hands alone will tear it.
Bread lame One deep, confident cut. A loaf this heavy needs a sharp blade — diced cheese near the surface will drag a dull one.
Metal roasting tray Sits on the rack below and takes the water for steam. Never glass — it will shatter.
Wire cooling rack This loaf needs a full cool before slicing or the melted cheese smears.

Method

Brown the onions (day before, or the morning you mix)

Slice the onions thin and add them to a heavy skillet with the oil over medium-low heat. No salt here — the dough and the cheese bring plenty.

Cook 45–60 minutes, stirring every few minutes. They will release water, collapse, then slowly turn deep amber and jammy. Don't rush this with high heat — you want sweet and soft, not scorched and bitter. 720 g raw cooks down to roughly 230 g.
Cool completely. Spread them on a plate and refrigerate if needed. Warm onions will slack the dough and throw off your fermentation — this matters more than it sounds.

Day 1 — mix and ferment

Feed your starter the morning you bake so it's lively when you mix.
Mix the dough. Whisk the starter into the lukewarm water to loosen it, then add both flours and mix by hand until no dry flour remains. Hold the salt back. Cover and rest 1 hour.
Add the salt. Sprinkle it over and squeeze and fold it through until fully worked in. The dough tightens slightly.
Stretch and fold — every 30 minutes, 4 sets. Wet hand, grab one side, stretch up, fold over the center, quarter turn, repeat around. Over these 2 hours the dough goes from shaggy to smooth and elastic.
Fold in the onions and cheese on the last set. Spread the dough out, scatter the cold onions and the 240 g of diced Jarlsberg across it, then fold it up and over itself until they're evenly distributed. Work gently — the gluten is already built and you don't want to tear it.
Bulk ferment until risen 30–50%. Roughly 4–6 hours total from mixing, depending on your kitchen. The dough should look domed and jiggly with bubbles along the sides. Watch the dough, not the clock.
Divide in two. Tip the dough onto a lightly floured surface and cut it into two equal pieces, about 810 g each. Round each one loosely into a ball.
Bench rest 20–30 minutes, uncovered. Don't skip this — the dough needs to relax before final shaping or it will fight you and tear.
Shape each piece into a taut round, pulling it toward you against the counter a few times to build surface tension.
Into the bannetons, seam-side up, in linen cloths dusted generously with rice flour.
Cold retard 12–16 hours in the fridge. The cold firms the dough so it scores cleanly and springs high, and it deepens the flavor.

Day 2 — bake

Preheat hard. 45–60 minutes ahead, put the perforated baking tray on the middle rack and the metal roasting tray on the rack below, and heat the oven to 250°C / 480°F.
Score the cold loaves. Turn them out, dust off the excess flour and make one confident deep cut down the length of each with the lame.
Bake with steam, 20 minutes. Slide both loaves onto the hot tray, pour a cup of boiling water into the roasting tray below and close the door fast.
Drop to 200°C / 390°F, remove the steam tray, and bake 15 minutes more until the crust is deep brown and the cheese at the surface has caramelized.
Cool completely on a wire rack — at least 2 hours. Slicing warm drags the melted cheese through the crumb.

Notes

Chef's tip — cold onions, added late. Two things decide whether this loaf works. The onions go in cold, because warm onions soften the gluten and push fermentation unevenly. And the inclusions go in on the last fold, not the first — nearly 500 g of onion and cheese against 600 g of flour will tear a gluten network that hasn't been built yet. Build the dough first, then load it.

Two loaves, not one. We divide this dough rather than baking one large boule. Smaller loaves bake through more evenly with this much inclusion, and you get twice as much crust — which is where the browned onion and caramelized cheese live. Temperatures and times stay exactly the same.

No salt on the onions. The dough already carries 2.5% salt, and 240 g of Jarlsberg brings a good deal of its own. Salting the onions on top of that tips the whole loaf over. Onions and oil, nothing else.

Any firm cheese works. The 240 g of Jarlsberg gives the sweet, nutty note that suits browned onion, but Gruyère, Emmental, Comté or a sharp cheddar are all excellent here. Keep the weight the same and cut it into ¼-inch dice — shreds melt out and disappear into the crumb.

About the flours. Landhvete and emmer are both heritage wheats — sifted, so not quite whole grain. Outside Scandinavia, bread flour stands in for the landhvete, and sifted spelt for the emmer. Emmer flour is worth seeking out from a specialty mill if you can; it brings a mild sweetness that plain wheat doesn't.