The bananas nobody wants are the right ones
This is usually presented as a thrifty way of using up fruit that has gone too far, which makes it sound like a compromise. It is not. Black bananas make a better loaf than fresh ones by a wide margin, and three separate things are happening inside them.
Starch turns into sugar. A green banana is largely starch and tastes of almost nothing. Enzymes break that starch down into simple sugars as it ripens, which is why a black banana is sweet to the point of being difficult to eat on its own. That sweetness goes into the loaf, so you need less added sugar and you get more banana flavour.
The structure collapses. Pectin holds plant cell walls together, and it breaks down as the fruit ripens. A ripe banana mashes into the batter and disappears; a firm one stays as lumps of fruit sitting in cake, which is a different and worse texture.
The aroma concentrates. The compounds that make banana smell of banana, mostly isoamyl acetate, build up sharply during ripening. That is why an overripe banana can be smelled across a room and a yellow one cannot.
If yours are not there yet, put them on a tray skins on and bake at 170°C for fifteen minutes. The skins go black, the flesh softens and sweetens, and it is a real shortcut rather than a way of pretending.
Fold, and stop at the streak
Everything up to the flour going in can be beaten as hard as you like. After that, fold.
A banana bread batter has plenty of liquid and plenty of flour, which is a good environment for gluten. Gluten is what makes bread chewy and what makes a cake tough, and the only control you have over it is how much you stir. Fold with a spatula, cutting down through the middle and turning the bowl, and stop the moment the last visible streak of flour goes.
It will look slightly under-mixed. That is the correct appearance, and the loaf that comes out is noticeably lighter than one that was beaten smooth.
Raw in the middle is a shape problem
This is the standard banana bread failure and it has nothing to do with the recipe. A loaf tin is deep and narrow, so the batter sits in a tall column and the centre is further from every hot surface than in any other shape you bake.
That means the outside reaches done well before the middle does. Left alone, you get a dark crust, a dry edge and a wet seam through the centre.
Two things fix it and they work together. Bake at 170°C rather than 180, which slows the outside enough for the middle to catch up. And as soon as the top is as brown as you want it, lay a loose sheet of foil over the tin. The loaf carries on cooking and the crust stops colouring.
Test with a skewer into the centre. A crumb or two clinging to it is right; wet batter is not. Start testing at fifty minutes and expect to add ten or fifteen.
It is a cake and the name is an accident
No yeast, no kneading, raised with bicarbonate of soda, mixed as a batter, and carrying enough sugar and fat to sit comfortably alongside a sponge. By every technical measure this is a cake.
It is called bread because it is baked in a loaf tin and sliced, which is the same reason soda bread and courgette bread and most things labelled a quick bread carry the name. It is worth knowing mainly because it explains the method: if you treat it like bread and knead it, you will get something you could resole a shoe with.
The mashing is the job worth handing over
Almost everything up to the oven belongs to a child here, and peeling and mashing four black bananas with a fork is the single most popular job in this entire section. It is messy, there is no way to do it wrong, and leaving lumps in is actively encouraged.
The folding is the one worth explaining rather than just supervising. Stopping early is a real skill and it feels wrong every time, and a loaf that comes out light because somebody put the spatula down is a better argument than anything written here.
Common questions
How ripe should bananas be for banana bread?
Black, or as close to it as you can bear. As a banana ripens, enzymes convert its starch into sugar, the pectin holding the cell walls together breaks down so it mashes smoothly, and the aroma compounds that make banana taste of banana concentrate sharply. A yellow banana gives a pale, drier loaf that tastes vaguely of cake. The ones nobody in the house will eat are the correct ingredient.
Can you use bananas that are not ripe enough?
Bake them first. Whole, skins on, on a tray at 170°C for about fifteen minutes, until the skins have gone black and shiny and there is liquid seeping out. The heat converts the starch in much the way a few more days on the counter would. It is not quite identical to genuinely ripe fruit, and it is far better than pressing on with yellow ones.
Why is my banana bread raw in the middle?
A loaf tin is deep and narrow, so the outside is done long before the heat reaches the centre. Two fixes and you can use both. Drop the oven to 170°C rather than 180, which gives the middle time to catch up, and lay a loose sheet of foil over the top as soon as it is brown enough, which stops the crust going further while the centre finishes. Test with a skewer, not a clock.
Why is my banana bread tough?
It was mixed too much after the flour went in. This is a batter, not a dough, and every stir past the point where the flour disappears develops gluten and tightens the crumb. Fold with a spatula rather than beating, and stop at the last visible streak. Mashing the bananas is where the enthusiasm should go, and even there a few lumps are an improvement.
Should banana bread have lumps of banana in it?
A few, yes. Mashing to a completely smooth puree gives an even loaf that tastes uniformly of banana, and leaving some texture gives you pockets that are noticeably more intense when you hit one. It is a preference rather than a rule, and it is the rare case where less effort produces the better result, so it is worth knowing that it is a choice.
Can you freeze banana bread?
Three months, and it is worth slicing it before it goes in. A whole frozen loaf has to be defrosted as a whole loaf; individual slices separated by greaseproof come out one at a time and are ready in twenty minutes, or straight into a toaster. Wrap it well: banana bread is moist enough that freezer burn shows up quickly on an unwrapped surface.
Is banana bread cake or bread?
Cake, by any technical measure, and the name is a historical accident. It has no yeast, it is raised chemically with bicarbonate of soda, it is mixed as a batter rather than kneaded as a dough, and the sugar and fat content are firmly in cake territory. It is called bread because it is baked in a loaf tin and sliced, which is the same reason for soda bread and for most things called a quick bread.
What can children do in this recipe?
Nearly all of it up to the oven. Peeling and mashing the bananas is the best job on the list and the one most likely to be fought over. Weighing, whisking the dry ingredients, beating the wet and folding the two together are all theirs, and the folding is a useful lesson in stopping early. The oven work is not, because the loaf is heavy, the bake is an hour and it needs checking mid-way.