Lung. You can’t buy lung in the US.
There goes the sofritto. Friend of mine remembers the fun of helping his very Italian grandma in the kitchen. She would entrain him by pulling on the tendon in chicken feet and blowing up the lungs. He claims the lungs are nice and spongey and really soak up the sauce.
He was amazed to find that in tally, they don't eat the lungs.