Baking guide · 07

How to make a basic sourdough loaf

A plain white boule leavened only by natural starter: the formula, the timeline from active starter to cooled loaf, and what each stage should look like.

Formula (one round loaf)

IngredientWeightBaker’s %
Bread flour450 g100%
Water324 g72%
Sourdough starter (levain)90 g20%
Salt9 g2%

Counting added water only, hydration is 72%. Counting the flour and water in a 100% starter, total hydration is about 74.5%. The maths is in how to calculate dough hydration.

Before you start: use an active starter

Use the starter 4–8 hours after feeding, when a spoonful floats in water. Ratios and readiness cues are in how to feed a sourdough starter.

Timeline and what to look for

StageWhat to doCheckpoint
1 MixMix active starter, water and flour; hold back the saltEvenly mixed, no dry flour left in the bowl
2 Rest · 40 min · 25°CCover and let the gluten develop on its own, then mix in the saltSalt fully worked in
3 Bulk · about 5 h · 25°CCover at room temperature; with wet hands, stretch and fold every 30 minutes, 3–4 timesAbout 1.5× in volume, a web of bubbles at the surface and edges
4 ShapeTurn out, pat gently to release some gas, fold the edges to the centre into a tight round, seam-side down into a floured bannetonTaut surface that springs back slowly
5 Cold proof · about 12 h · 5°CBag and refrigerate overnight — easier to score, more flavourA poke fills back about halfway: ready to bake
6 ScoreTurn the cold dough onto parchment and make one quick, deep slashOne clean cut — don’t saw back and forth
7 BakePreheat a covered Dutch oven at 250°C for 45 min; bake covered 20 min, then uncover, lower to 230°C and bake 20–25 min moreScore opens with an ear, crust deep brown
8 Cool · at least 2 hCool completely before slicingFully cool inside

Three common mistakes

No banneton or Dutch oven?

A cloth-lined bowl works as a banneton. Without a Dutch oven, bake on a sheet pan with a tray of hot water in the oven for steam.

What to write down

Sourdough has a lot of moving parts: starter state, dough temperature, bulk time and rise, cold-proof time. At the very least note how much the dough rose in bulk — if the loaf comes out dense or flat, it’s what tells under- from over-proofing. See bread didn’t turn out? How to review it.

Bake this one in the app

This Basic White Sourdough is one of BakeMemo’s recipes. Follow it step by step with a checkpoint and a common pitfall on every step, run a timer on any step, then do an after-bake check. 62 recipes and your first three bakes are free, no sign-up.

Download on theApp Store — free

Formula and steps come from BakeMemo’s built-in recipe “Basic White Sourdough”. Times and temperatures are a starting point — go by how your dough looks.