"Tenement house in a shower of rain” was old New York City restaurant slang for “beefsteak and gravy.” The term was first cited in an 1888 newspaper, reporting on the strange orders at a restaurant on Ann Street.
The slang term had almost disappeared by 1920.
Hudson River Valley Heritage Historical Newspapers (NY)
24 March 1888, The Rockland County Journal (NY), “Waiters’ Queer Orders,” pg. 6, col. 1:
A NEWS reporter went into a restaurant on Ann street yesterday and after having given his order to the waiter asked him what was the meaning of the jargon waiters usually shriek at the cook.
By furthering questioning the reporter learned that “Put one in the pan” meant meat pie, and that a “Tenement house and a shower of rain” interpreted was the same as Hamburger steak and a fried onion.
-- N. Y. News.
19 March 1923, Akron (OH) Beacon Journal, “Restaurant Slang Rapidly Going Out of Date; Akron Waitress Had Patrons Right,” pg. 8, cols. 6-7:
Beefsteak and gravy had another name, according to the early training of the waiters, and in some places it was called, or yelled, “A tenement house in a shower of rain.” Just what the connection between the swimming steak and the rain soaked tenement house was could never be learned, and the waiters themselves professed to know nothing of its origin. It was that, and that was all there was to it.
20 March 1923, Akron (OH) Beacon Journal, “Gastronomic Lament,” pg. 4, cols. 5-6:
To be reminded of a “tenement house in a shower of rain,” was like calling to my mind my younger days when joy seemed to be limitless, and to me, an exiled New Yorker who once knew the Bowery as well as I know Portage Path, the story was like an obituary of a very close friend.
Beefsteak and gravy (tenement house in a shower of rain) was never prepared as well as in any other place. ("Dirty Biily’s” on the Bowery.—ed.)
The story of the passing of restaurant slang revived many old and fond memories to the writer.
EXILED NEW YORKER.