Prickly Lettuces! Looks like a healthy one. I have eaten these steamed with butter and raw. Good either way. A great medicine too.
One of my earliest teachers of wild plants, Jon Young says "When you start to learn the wild plants you gotta get into bitter and sour."
I have noticed Prickly Lettuces and
dandelions are much sweeter when growing in a
hugel bed or other mineral rich garden system.