To make the clearest Consomme with Herb Dumplings, always simmer stock over lowest possible heat, and avoid stirring.
Place chicken and bones in a large stockpot and cover with cold water. Bring to a boil; let simmer 5 minutes. Drain and rinse.
Return chicken and bones to the pot and add all remaining ingredients except for unpeeled onion. Bring slowly to a boil and simmer gently.
After 20 minutes, remove chicken quarters, pull off meat, and return bones to pot. Reserve chicken meat for another use.
Cook onion without fat, cut sides down, in a heavy skillet for about 20 minutes, or until completely blackened. (The blackened onion will add color to the finished consomme.) Add onion to stock; continue simmering for 4 to 5 hours, skimming off foam as necessary.
Strain stock and discard solids. Let stock cool completely, then cover and refrigerate overnight. The next day, remove and discard any fat that has risen to the top.