green pea soup vs potage St. Germain

green pea soup and potage St. Germain both are nouns.

Word	Noun	Adjective	Verb	Adverb
green pea soup	Yes	No	No	No
potage St. Germain	Yes	No	No	No

As nouns, green pea soup and potage St. Germain are synonyms defined as:

green pea soup and potage St. Germain: made of fresh green peas and stock with shredded lettuce onion and celery

green pea soup (noun)	potage St. Germain (noun)
made of fresh green peas and stock with shredded lettuce onion and celery	made of fresh green peas and stock with shredded lettuce onion and celery