On page 34 (of the PDF scan), Bras explains his vegetable broth. He does not give a ratio. He says: "Take the skins of carrots, the green tops of leeks, a handful of hay from the farm. Simmer until the liquid tastes of the field, not of the pot." You must iterate. The PDF work requires you to fail three times before you succeed.
For those interested in accessing "Essential Cuisine" in PDF format, there are several options available: essential cuisine michel bras pdf work
Many recipes call for specific wild herbs and flowers that Bras foraged himself. On page 34 (of the PDF scan), Bras
Why is this PDF so sought after? Because the book is a failure as a traditional cookbook. the green tops of leeks