Peperoncino is the generic word for dried chilli in Italy. They’re great for throwing in anything to give it a little bit of a zizz. Unlike some of the dried chilli flakes you buy in UK supermarkets, these have a kick; when you flake them up on your hand you can feel the heat.
If I’m making a classic tomato sauce for pasta, I’ll fry off the onions and garlic, then crush in peperoncini, then add the tomatoes so they get that heat through.