“Boula-Boula” is more than just a cheer at Yale University. “Boula” (also called “boula-boula” and “boula soup” and “boula gratinee”) was a widely popular soup at New York City’s upscale restaurants and hotels in the 1930s, such as the Plaza Hotel. “Boula” (the origin of the name is unexplained) is a combination of green pea soup and turtle soup, with sherry seasoning added and topped with unsweetened whip cream.
 
“Boula” is rarely found in New York City (or anywhere else) today, as turtle soup is seldom available in kitchens.
 
 
13 November 1931, Hamilton (OH) Daily News, “Favorite Recipes of Famous Women” by Peggy Wood, pg. 8, col. 4:
Then Boula au gratin,...
(...)
For the boula, boil together for a few minutes one pint of turtle soup and one pint of cream of pea soup. Pour in cups and add a little sherry seasoning. Then spread unsweetened whip cream on top and glaze under the broiler.
 
26 March 1932, Oakland (CA) Tribune, “Talk of New York” by Karl K. Kitchen, pg. 9, col. 4:
To make up for his long wait, perhaps, I ordered an exceptionally good dinner, including some of the special dishes of the hostelry: Boula gratinee, as the mixture of turtle and pea soup is called;...
(Plaza Hotel—ed.)
 
Tips on Tables:
Being a guide to dining and wining in New York at 365 restaurants suitable to every mood and every purse
by George Ross
New York, NY: Covici Friede Publishers
1934
Pg. 193:
BELL MANSION 312 West 75th Street (West End Avenue and Riverside Drive)
After the caviar comes boula, a deliciously prepared soup made from such singularly incongruous ingredients as turtle and pea soups and sherry, topped off with a spoonful of whipped cream and then baked in the oven.
Pg. 218:
THE KING’S TERRACE 240 West 52nd Street (Broadway and 8th Avenue)
BACK in the old days, when Utah was still a nonentity and they even let women stand up at bars, the King’s Terrace was the ne plus ultra of the uptown saloons.
(Pg. 219 —ed.)
For dining at the King’s Terrace did, and still does, consist of a veritable parade of palatable delicacies such as boula gratinee (pea soup helped along with green turtle and sherry), lobster cardinal, and Virginia Ham Eugenie.
     
1 February 1935, Middletown (NY) Times-Herald, pg. 10, col. 2:
For the plain boula, combine chicken stock (you may use the canned stock) with puree of green peas (also canned, if desired), using sufficient stock to make of the thickness of the usual pea soup. To this add the contents of a small can of turtle meat, cut in small dice. Season well, heat thoroughly, and when ready to send to the table add a tablespoon of sherry for each serving. This will make a delicious, finely flavored soup. But for added delicacy, try the boula gratinee.
 
Mix with pea puree an equal quantity of chicken stock and cream; add the diced turtle meat and seasoning and heat thoroughly. When ready to serve, pour into individual soup cups, top with whipped cream and glaze quickly under the broiler. Serve with little cheese chips of Melba toast.
 
October 1935, Better Homes and Gardens, pg. 58, col. 2:
One Speedy Soup
“A crowd of us dropped in on a friend one day, giving only 10 minutes’ notice.  By the time we arrived, she had this good soup all ready.”
 
Boula-Boula
1 can mock turtle soup
1 can chicken bouillon (Bouillon-Bouillon?—ed.)
1 can pea soup
2 cups water
1/2 cup heavy cream, whipped
   
Combine the soups and the water in a sauce pan.  Bring slowly to the boiling point, then simmer gently for 5 minutes.  Whip the cream until stiff and pile on whipped cream on a pie plate or baking dish.  Place directly under the broiler flame of a hot oven.  Broil cream quickly until pale golden crust forms in spots.  Place the hot soup in bouillon cups and carefully spoons a portion of the broiled cream on each serving.  Serve immediately.  Serves 10.—_Mrs. Mable Holmes_, Hamilton Square, New Jersey.
     
23 December 1935, Oakland (CA) Tribune, “New York” by George Tucker, pg. 30?, col. 7:
NEW YORK, Dec. 23.—A bit of a story here—a bit of a story there— that’s New York.
   
There was a luncheon J. O. Voit gave for Raould Ricoult the other day at the Sherry-Netherland cafe-bar, and all during the luncheon the honor guest took notes on a little memo pad by his plate.
   
When the boula (a combination green turtle and pea soup) was served he scribbled a new sheet and thrust it into his pocket. 
 
Google Books
Where to Dine in Thirty-Nine
by Diana Ashley
New York, NY: Crown Publishers
1939
Pg. 93:
CHEF’S RECIPE: BOULA GRATINE, a soup famous at the Plaza. Joseph Boggia, Chef de cuisine. 1/2 cream green pea soup, 1/2 clear green turtle soup, add 1 tbls., per cup, of diced turtle meat, add…
     
Google Books 
Dining in New York With Rector:
A Personal Guide to Good Eating
by George Rector
New York, NY: Prentice-Hall, Inc.
1939
Pg. 67:
...then boula gratinee, a mysterious compound of green turtle and green pea that turns into a soup with a bouquet as well as a flavor. 
 
4 October 1945, Walla Walla (WA) Union-Bulletin, pg. 16, col. 4:
Boula Soup
1 can condensed green pea soup
1 tablespoon Sherry
1 can green turtle soup
Whipping cream
Mix equal quantities of condensed green pea and green turtle soup with the Sherry (even if the green turtle soup already contains Sherry). Heat thoroughly but do not boil. Pour into individual heat-proof soup pots. Put a bit of salted whipped cream on top of each and brown lightly in the oven or under the flame.
 
Google Books
Vogue’s Book of Etiquette
by Millicent Fenwick
New York, NY: Simon and Schuster
1948
Pg. 326:
boula-boula (half fresh pea puree and half rich turtle soup)
 
24 December 1955, New York (NY) Times, pg. 16:
Around about midnight at this time of year, many New Yorkers feel they have been slipping too much and eating too little. To any who may be in your household, offer an appetizing dish. These things come to mind: Minute steaks, boula boula (combine canned green pea and canned turtle broth in equal parts),...
 
22 March 1956, New York (NY) Times, “Chef’s Secret,” pg. 30:
The Passy, also on the East Side, is known for its boula boula. Heat together in equal quantities turtle broth and green pea soup. Add dry sherry to taste. Top with whipped cream.
 
16 July 1957, New York (NY) Times, pg. 40:
before the salmon, which was served cold in aspic, there was a hot boula-boula, fresh turtle soup, concocted with fresh turtle meat, a puree of fresh peas and a dash of sherry. Whipped cream was piled atop the individual servings of soup and the dish went under the broiler till the cream was golden brown.
(Nino’s Sports Afield Room, 10 East Fifty-second Street—ed.)
 
5 August 1965, Lima (OH) News, pg. 24, col. 6:
FAVORITE RECIPES OF
JACQUELINE KENNEDY
BOULA-BOULA
(American Soup)
2 cups freshly shelled green peas
1 tbsp. sweet butter
Salt and white pepper
2 cups canned green turtle soup
1 cup sherry
1/2 cup whipping cream
   
Cook the green peas in boiling salt water. Strain through a fine sieve or an electric blender to get a puree; reheat it. Add one tablespoon sweet butter, salt, and white pepper to taste. Blend with the green turtle soup and one cup of sherry. heat to just under the boiling point. Put the soup into serving cups. Cover each cup with a spoonful of unsweetened whipped cream. Brown topping under the broiler.
 
7 December 1983, New York (NY) Times, Q&A, pg. C7:
Q. When I was a child my mother often served a soup called boula-boula if she wanted to impress her guests. Can you tell me how it was made and do you know the origin of the name?
A. In my childhood, as in yours, boula-boula was a dish to be served on fancy occasions. it was made with a blend of two canned soups, a cream of green pea and a green turtle. As a finishing touch my mother always added a dollop of whipped cream, and the dishes were run briefly under the broiler until the cream was lightly browned.
 
I have never found the definitive volume that points out the exact origin of the soup. In “The Food of the Western World” (Times Books, 1976), Theodora FitzGibbon says that it is an American soup but adds, oddly enough, that it “originally came from the Seychelles.” At least one reason for the diminished popularity of the soup is that in many parts of the world it is forbidden by law to trap green turtles.
   
Google Books
Fashionable Food: Seven Decades of Food Fads
by Sylvia Lovegren
Chicago, IL: University of Chicago Press
2005
Pg. 78:
Boula has a more documented history than does Mongole soup. It was known in the United States as early as the 1830s (1930s?—ed.) and was made more recently by President Kennedy’s chef, Rene Verdon. Although Verdon said that the Kennedys jokingly renamed the soup boula boula, after the Yale song, it was frequently called that longbefore the 1960s. In the Thirties, boula, like Mongole, was frequently made with canned soups. Obviously it can be made from fresh ingredients…if you can come up with your own green turtle.
Pg. 79:
BOULA
In Much Depends on Dinner (1939), Mary Grosvenor Ellsworth said, “M. Derouet, the maitre of the Chemists’ Club, told me about this one. He serves it to special stag banquets and invariably gets cheers.”
1 (15-ounce) can condensed pea soup
1 (15-ounce) can condensed green turtle soup
2 soup cans water
1/4 cup dry sherry
1/2 cup heavy cream
Pinch of salt
mix the soups and water together. Bring to a boil and let bubble for a few minutes. Remove from the heat and stir in the sherry. Pour the soup into individual ovenproof soup bowls. Whip the cream with the salt until firm peaks form. Put a blob of cream on top of each serving and brown under a hot broiler.
MAKES 6 SERVINGS