Step 1Cut the celery in thirds. Peel and halve the onion and garlic. Place the chicken carcasses in the Instant Pot or a pressure cooker.
Step 2Add water until you fill about two thirds of its capacity. Add the celery, onion, garlic, bay leaves, allspice, vinegar (or use lemon juice), salt and pepper.
Note: Apart from these vegetables you can use carrots, leeks, parsnip, parsley roots, or celeriac.