“Pea soup and jonnycake make a Frenchman’s belly ache”

Entry in progress—B.P.
 
Wikipedia: Pea soup
Pea soup is soup made, typically, from dried peas. It is, with variations, a part of the cuisine of many cultures. It is greyish-green or yellow in color depending on the regional variety of peas used; all are cultivars of Pisum sativum.
 
Pea soup has been eaten since antiquity; it is mentioned in Aristophanes’ The Birds, and according to one source “the Greeks and Romans were cultivating this legume about 500 to 400 BC. During that era, vendors in the streets of Athens were selling hot pea soup.”
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Old Vermonters said, “Pea soup and Jonnycake/Make a Frenchman’s belly ache.”
 
Wikipedia: Johnnycake
Jonnycake (also spelled “johnnycake,” johnny cake, and “journey cake”) is a baked cornmeal flatbread, and was a popular American pioneer staple food. The dough was set on a wooden board or barrel stave and placed at an angle in front of an open fire to bake. The dough, made of cornmeal, salt, and water, was seldom sweetened since sugar was expensive and in short supply in early colonial America and on the frontier. “Johnnycake” likely stemmed from “Journey-cake”, as the Rhode Island accent omits the term’s “r” sound in everyday speech.
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Old rural New England saying “Pea soup and Jonnycake, makes a Frenchman’s belly ache”
 
Google Books
What They Say in New England:
A book of signs, sayings, and superstitions
Collected by Clifton Johnson
Boston, MA: Lee and SHepard Publishers
1897
Pg. 179:
Pea-soup and Johnny-cake
Make a Frenchman’s belly ache.