The course · free

Sixteen Loaves: from banana bread to rye sourdough

Sixteen loaves, and each one changes exactly one thing from the loaf before it. Start with banana bread. Finish with a long-ferment, high-hydration rye sourdough. One pan, one oven setting, no Dutch oven.

The whole course is free, with no account and no checkout. The one thing it asks for is how each loaf went. Every loaf ends with a short form. Tell us what worked, what confused you, and send a photo if you have one. That is how the course gets better.

Start at Loaf 1 →

The sixteen loaves

How Sixteen Loaves works

You already know how to make banana bread. That is Loaf 1.

Sixteen loaves later you are making a long-ferment, high-hydration rye sourdough, and at no point did you take a leap of faith, because every loaf changes exactly one thing from the loaf before it. One ingredient, or one technique. Never both, never two.

Every one of them is a real loaf you eat. There is no loaf that exists only to get you to the next one.

What never changes

Four things are frozen across all sixteen loaves.

Frozen	Value	Why
Total flour	400 g	Every percentage in every loaf is a percentage of this one number, so the loaves are comparable
Salt	8 g, which is 2%	Salt is the one seasoning decision in bread and 2% is the answer. Settle it once and it stops being a variable
Vessel	one 9 x 5 inch (23 x 13 cm) loaf pan	No shaping tension to lose, no 500F (260C) lid to lift, no scoring required
Oven	375F / 190C	One setting, sixteen breads

You never need a Dutch oven to finish this course. The endpoint is a pan bread. Scoring, steam and cast iron are a real skill and they get their own optional branch off Loaf 11, but they are not a step on the way to anything here.

The one rule

Change one thing. Bake it. Bake it again. Then move.

One good loaf is luck. Two in a row is a skill.

If you change two things and the loaf comes out worse, you have learned nothing, because you cannot tell which change did it. That is not a discipline problem, it is an information problem, and it is why most people's baking stops improving after about five loaves.

Every gate in this course is something you look at. Times always come with a temperature, and the time is context for the look, never the instruction. "Risen by half at 75F / 24C, usually about 2 hours" means watch the dough. A recipe that just says "rise 2 hours" is telling you about its own kitchen, not yours.

The thing nobody tells you about hydration

Banana bread pours. Sourdough sits there in a lump. So the road from one to the other must run downhill in water, right?

No. Banana bread's 220 g of banana carries 165 g of water, and its two eggs carry 75 g more. That is 240 g of water on 400 g of flour: 60% hydration, a perfectly ordinary, slightly stiff bread dough. A lean bread dough and a banana bread batter sit at the same hydration.

What makes the batter pourable is 41% sugar and 20% fat. Sugar dissolves into the water and competes with the flour for it. Fat coats the flour proteins so they cannot link into a network at all. Take those two away at the same water and you do not get a batter, you get the stiffest dough in this whole course. That happens at Loaf 6 and it surprises everyone.

So the water rule here runs the other way from what you would guess:

60% to 70% to 85%. Hydration only ever climbs, and it never once steps back.

The sixteen loaves

#	The loaf	The one thing that changed	Hydration	Leavening
1	Banana bread	baseline	60%	baking powder
2	The same loaf without the banana	banana out, 165 g water in	60%	baking powder
3	The sugar comes out	164 g sugar out	60%	baking powder
4	Yeast takes over the lift	baking powder out, 6 g instant yeast in	60%	instant yeast
5	The egg comes out	egg out, water up by its 75 g	60%	instant yeast
6	The oil comes out	80 g oil out	60%	instant yeast
7	Kneading	stirring becomes kneading	60%	instant yeast
8	Shaping	pressed in becomes shaped in	60%	instant yeast
9	More water	water 240 g to 280 g	70%	instant yeast
10	Folds instead of kneading	kneading becomes stretch and fold	70%	instant yeast
11	The cold night	counter proof becomes fridge proof	70%	instant yeast
12	Starter instead of yeast	yeast out, 80 g starter in	70%	sourdough starter
13	Rye	280 g of the wheat becomes rye	70%	sourdough starter
14	The folds come off	folding stops	70%	sourdough starter
15	High hydration	water 280 g to 340 g total	85%	sourdough starter
16	The long cold	12 hours cold becomes 24	85%	sourdough starter

Read down the hydration column and the whole argument is visible: eight loaves at 60%, six at 70%, two at 85%, and not one step backwards.

Two bits of sequencing that look arbitrary and are not

Sugar leaves at Loaf 3, before yeast arrives at Loaf 4. At 41% sugar the dissolved sugar pulls water away from the yeast osmotically. Yeast slows noticeably above about 10% sugar, which is why commercial bakeries keep special strains for sweet doughs. Put ordinary instant yeast into a 41% sugar batter and it makes very little gas, very slowly. That version would bake a brick, and every loaf here is one you eat.

Loaf 1 uses baking powder, not the baking soda most banana bread calls for. Soda needs an acid to work against, and in banana bread that acid is the banana. Pull the banana at Loaf 2 and soda would have nothing left to react with, so removing one ingredient would have silently forced a second change. Baking powder brings its own acid, so it survives Loaf 2 untouched and leaves only when we choose, at Loaf 4.

That is what a one-variable course costs. You pick Loaf 1's ingredients for what they let you do at Loaf 6.

Where to start

Loaf 1. Even if you have made sourdough before. The point is not the banana bread, it is baking every loaf twice and the habit of moving one variable at a time, and that habit is the entire reason this works.

Bake it twice. Then move on.

Start at Loaf 1: banana bread →