To get absolutely clear, pure beef broth: heat dry cast iron skillet, sear meat till the brown color you want in the broth, about a minute each side. Put meat in dutch oven with celeriac, covered with cold water, bring to slow boil 2 hours.

Add 4 cups cold water to solidify foam and fat on top, skim off. Cut meat in bite size pieces, add back to broth. Add sliced carrot, twig of parsley, sliced leaves of red, white, yellow swiss chard and stems. Bring to a slow boil, turn down to simmer, cover the lid. Simmer three hours. Taste every hour till perfect.