Spread the onions on the bottom of a slow cooker.
Top the onions with the pork in an even layer.
Cover with salsa verde.
Cover and cook for 8 hours on Low or 4 hours on High.
Shred the pork (either in the slow cooker or on a cutting board) and stir back into the sauce in the slow cooker.
Serve in tortillas, with cornbread, with tortilla chips, over rice, with beans, whatever works!
