What is this piece and what to do with it

Hi I've been cooking pork belly for a long time but I've never found out what this piece is and what to do with it. I usually cut it along with the pork belly into cubes and stew sweet/sour style but this piece specifically isn't very good stewed due to being low fat and fibrous. I tried cutting it off and into very thin slices against the grain and stir frying very lightly but it's still isn't great and gets tough super quickly. Please let me know what is the name of this piece (it's right above the pork belly but doesn't cover the whole pork belly usually skin-fat-meat-fat-meat-this piece). Thank you!