Yoghurt cuts sweetness and richness, tempers spice, and makes a dish sing.
My father always cooks more polenta than he needs for a meal. The excess he spreads on an oiled surface and chills. Next day, he cuts out chunks, fries them in olive oil and serves with salad.
Most fish require a short cooking time, but cephalopods are the exception to this fishy rule. As with some cuts of larger land beasts, the longer they're cooked, the more tender they get.