Adapted from Yoshida Morihide’s banana bread — a baking-soda-and-powder loaf with ~36% ripe banana, loosened with a little oil and cream for a moist, open crumb. Use the ripest, most black-spotted fruit you have. Warm from the oven it’s fragrant and fluffy; the next day it settles moist and cohesive.

Ingredients

   
65g unsalted butter, softened
3g salt
112g light brown sugar (for cassonade)
150g whole egg (3 large)
125g cake flour
125g all-purpose flour
5g baking soda
5g baking powder
56g honey
442g very ripe banana (black-spotted), mashed
40g neutral oil
52g heavy cream (or milk)
52g walnuts, chopped (optionally toasted)

Steps

  1. Butter a 9×5-inch loaf pan and line with parchment. Preheat the oven to 340°F (or start at 350°F to set the top, then drop to 325°F after 15–20 minutes — see notes).

  2. Cream the softened butter, salt, and brown sugar 2–3 minutes until light.

  3. Beat in the egg gradually, then the honey. Whisk in the oil and cream until smooth. If it looks split, warm the bowl briefly or add a spoonful of the flour.

  4. Whisk the cake flour, all-purpose flour, baking soda, and baking powder together. Fold into the batter along with the mashed banana, mixing just until no dry streaks remain — don’t overwork it.

  5. Fold in the walnuts last.

  6. Scrape into the pan. Bake at 340°F until a skewer in the center comes out with a few moist crumbs (no wet batter) — about 55–70 minutes. Tent with foil around 35–40 minutes if the top browns before the center sets. The center should read 205–208°F internally if you have a thermometer.

  7. Cool in the pan 10 minutes, then turn out. Best the next day; eat within 1–2 days.

Analysis

Total batter weight: 1232g (banana is ~36% of it)

Component Amount %
Structure solids (flour + fruit/nut fiber) 268g 21.8%
Fat (butter, oil, cream, egg, walnut) 161g 13.1%
Sugar (brown sugar, honey, banana) 247g 20.0%
Liquid (banana, egg, cream, honey water) 507g 41.2%
Egg/nut/fruit/dairy protein 35g 2.8%

A quick bread loosened toward a lighter crumb. Banana still supplies most of the liquid and much of the sugar with no added milk, but a shot of oil and cream push fat to ~13% (from ~9% in the plain original), and baking powder joins the soda for extra lift — so the crumb opens up and eats moister. Structure stays high for a cake (~22%) because it still needs enough gluten to hold the heavy wet fruit without sinking, which is why the flour is a deliberate blend of cake (tender) and all-purpose (structure) rather than all of one.

Notes

  • Ripeness is everything. Use heavily black-spotted to nearly-black bananas — riper means sweeter, softer, and far more banana aroma, and the acid is what drives the baking soda. Underripe banana gives a bland, pale, under-risen loaf. Not there yet? See Ripening Bananas — and note the oven/microwave shortcuts soften without really sweetening, so nudge the sugar up if you use them.
  • Cassonade → light brown sugar. The original calls for cassonade (French unrefined cane sugar); light brown sugar is the clean 1:1 sub for its caramel/molasses note and moisture. Turbinado or demerara is more flavor-accurate but coarser — pulse it fine or it can stay gritty.
  • Oil and cream loosen the crumb. The plain Yoshida formula is lean on fat (~9%) and eats like a moist pound cake; the 40g oil and 52g cream here lift fat to ~13% and open it up. Oil stays liquid at room temperature so it reads looser and moister than butter alone; the cream adds fat, moisture, and a little richness. Milk subs for the cream for a lighter, less-rich loaf. Want it looser still? Melt the butter and just whisk everything (muffin method) instead of creaming.
  • The two-flour blend is deliberate. The original pairs a weak flour (薄力粉, cake) with a “medium-strong” flour (中強力粉, ~10.5–11.5% protein) — cake flour alone would be too fragile to carry this much wet banana and would gum in the center; all bread flour would go tough. All-purpose is the clean stand-in for the medium-strong half, giving an effective ~9.5–10% protein: tender but sturdy. In a pinch, all-AP (250g) works fine — this is a forgiving quick bread.
  • Soda and baking powder together. The soda needs the banana, honey, and brown sugar’s acid to fire, and it browns the crust; the baking powder adds the extra lift that opens the crumb. Whisk both evenly into the flour — a stray clump of soda leaves a soapy, yellowish spot. That’s the only real risk, and it’s low.
  • No 340°F on your oven? 340°F is just “between 325 and 350.” For a tall loaf, either bake straight at 325°F (add ~5–10 min, gentlest on the center) or start at 350°F for 15–20 minutes to set the domed top, then drop to 325°F for the rest — the “start hot, finish gentle” route gives good lift and a fully-cooked middle. Plain 350°F works too but browns fast, so tent earlier (~30 min) and watch the center.
  • Original vs our single-loaf bake. Yoshida bakes the plain version at 180°C (356°F) for 35 min, splitting the batter between two small shallow bread pans — split into two shallow masses, the centers heat fast, so a short, hot bake works. Baked as one tall loaf in a single 9×5, the center sits far from every surface, and 180°C would scorch the top before the middle set — so drop the oven ~25°F and roughly double the time, as above. Two small loaf pans? Use his original 180°C / 35 min.
  • Scaling down. The full recipe (~1232g) fills a 9×5 loaf (bakes tall — tent the top and give it the longer time). For a deep 6×3-inch round, scale to ~0.76× (butter 49g, brown sugar 85g, egg 114g, cake + AP 95g each, soda 4g, baking powder 4g, honey 43g, banana 336g, oil 30g, cream 40g, walnuts 40g) and bake ~55–70 min. For a standard 6×2-inch round, scale to ~0.55× (butter 36g, brown sugar 62g, egg 83g, cake + AP 69g each, soda 3g, baking powder 3g, honey 31g, banana 243g, oil 22g, cream 29g, walnuts 29g) and bake ~40–50 min.
  • Serving it as a cake. Lovely warm with lightly whipped or brown-butter whipped cream, a spoon of salted caramel, or vanilla/salted-caramel ice cream; caramelized banana and toasted walnuts on top push it fully into dessert.
  • Keeps a day or two. The oil and cream help it hold moisture a touch longer than an all-butter loaf, but ~36% banana still means it’s best day-of to next-day. Freezes well wrapped tight if you want to hold it longer.