Banana

A banana tells you everything you need to know by its skin. Green means starch, hard and chalky. Yellow means the starch has turned to sugar, soft and sweet. Brown spots mean the flesh has gone soft and syrupy, the cell walls breaking down further and any starch that was left finishing its turn to sugar. That's why a spotty banana tastes sweeter and smells stronger than a plain yellow one — the fruit is telling you exactly what stage it's at. Choose it by that skin, not by the calendar. If you need it firm, for frying or for a salad, take one that's still pale yellow with a green tip. If you need it for bread or a smoothie, wait for the spots.

Some people say a banana with black skin is spoiled. No — it's just further along, and the flesh inside is usually perfect, sometimes better than ever. That misconception sends good fruit into the bin and pushes people to buy bananas that are too green, and then wonder why the bread comes out dense and starchy instead of soft. One hundred grams gives you 89 kcal, 22.84 g of carbs, 1.09 g of protein, and 0.33 g of fat — numbers that barely change as the fruit ripens; only the taste does.