Given the task definition and input, reply with output. In this task, you have to identify the named entities (NER) which are the ingredients required given its directions. Named entities are the names of the items without their quantity.

Preheat your oven to 400 F., Spread chicken carcass, wings, and feet (if you have them), onion halves, garlic, and carrots on sheet trays and roast until carcass is deeply golden brown, about 30 minutes. Pour off the drippings and reserve them for another use (like gravy)., Add the roasted carcass, wings, feet (if using), and vegetables to a medium stockpot along with celery, thyme, bay leaf, and peppercorns. Add water until ingredients are just submerged. Bring this mixture up to a boil over medium heat and then reduce it to a simmer., Simmer, covered, for three hours. With about twenty minutes left, add the 1/2 lemon if you're using it., Simmer for twenty more minutes, and strain.
Carcass, yellow onion, head of garlic, carrots, celery stalks, thyme, bay leaf, black peppercorns, lemon, Salt