Roughly chop all vegetables. Add to large pot and cover with water. Cook over low heat for approximately 5 hours, keeping water levels high. Mash vegetables and simmer for a further ½ hour. Wait until broth cools and then strain (this way you don’t need to try and squeeze the water out).
Add whole chicken/lamb shanks to the pot and cook as above. Take meat from the bone and set aside before you strain the broth. Allow to cool in the fridge, you can them skim the fat from the top and use for cooking or discard.