You can experience this if you hit a coin with a hammer a few times.
So the flash could cook a chicken by slapping it
One thing to note, actually cooking something requires an application of heat over time. Instantaneous heat transfer will not cook, it will usually just burn.
Some people say you can use a nuke to cook a pizza if you put it in the right spot, but the same problem would apply.
Related, some guy did actually slap a chicken into being cooked. It was predictably disgusting:
There are so many weird assumptions here. There is more than a hand moving when a slap is performed.
A skilled slapper could put more of their body weight behind the slap. I’d assume at least 40 kg or even more as the average slap.
Not chicken, but someone tried hitting steak with drum pedals: https://m.youtube.com/watch?v=QFTCqnYk5Sw
