Save the receipt Revisiting a recipe from our archives Cakes that take eaters by surprise

Danetra Richardson of Swank Desserts remade a sweet potato surprise cake.

Jacqueline Bradham of Eutawville didn’t mince words when responding to a fellow reader of The News and Courier who in 1988 requested a “good winter cake” recipe. Supplying the recipe for Sweet Potato Surprise Cake, Bradham wrote, “This cake is real good.”

Since Bradham didn’t elaborate, it’s impossible to know what she considered surprising about the pastry, made with grated sweet potatoes and spread with coconut frosting. But at a time when recipes for tuna surprise were more common in cookbooks, the cake provided a tasty reminder of sweets’ capacity to upend eaters’ expectations and teased a trend ahead.

While cricket flour isn’t exactly flying off the shelf, many environmentalists haven’t lost their faith in insect-eating: According to a recent article in The Los Angeles Times, entrepreneurs are now promoting fried mealworms as an earth-friendly alternative to pork rinds. But 40 years ago, earthworms were being touted as the invertebrate to nosh: As more gardeners shunned chemicals, there was an overabundance of them. The Evening Post in 1976 ran a wire story about a national worm recipe contest; top prize was awarded to Applesauce Earthworm Surprise Cake.

Now that’s a surprise. At least since the Middle Ages, animal cameos have figured into the most shocking food items: A 16th-century Italian cookbook contained instructions for baking pies with live birds inside, a recipe which may have inspired the rhyme about four-and-twenty blackbirds. That kind of entertainment was echoed by the practice of hiding trinkets in cakes; the trick was ritualized in the American South by the Twelfth Night Revelers, who in the 1800s started slipping beans into the cakes served at their Mardi Gras parties. King Cakes are still sold with little plastic babies.

But during the same period, another kind of surprise cake emerged in the United States. As explained by Dr. Alvin Chase in his 1864 cookbook, which was outsold only by the Bible, “Flavor with lemon, and use sufficient sifted flour to make the proper consistence, and you will really be surprised to see its bulk and beauty.”

For about a century hence, American cookbooks, newspapers and magazines challenged their readers’ low opinion of simple ingredients and new food products with countless surprise cakes. “Here is a cake which should satisfy even in this day of high living expenses,” The Charleston Sunday News pledged in 1916. “It is a surprise in every way.” The surprise cake recipe called for nothing but butter, sugar, flour, baking powder, milk and vanilla.

In 1936, Mrs. J. Watson Shockley demonstrated a recipe for surprise cake at The Post and News and Courier Cooking School. The recipe was reprinted in an advertisement for Crisco, which was doubtless a sponsor of the program and the titular surprise. Twenty-five years after Crisco’s release, its makers were still fighting to persuade consumers that vegetable shortening was as flavorful as lard and easier on the gut. “Even if it’s a joke to the fellows, indigestion isn’t funny to me,” John tells Jean in a cartoon accompanying the recipe. In the next panel, he’s asking for another slice of surprise cake.

Along with innovations, scarcity bred surprises: In 1964, The Evening Post ran a recipe for Stormy Weather Surprise Cake in anticipation of a hurricane. Food editor Charlotte Walker advised readers to stock up on powdered gelatin and sponge cake so they could combine the two for a surprisingly delicious dessert in case of a power outage.

Bradham’s recipe for sweet potato surprise cake follows the basic surprise cake formula: It’s made with humble ingredients that might not immediately excite the taste buds. There’s no butter or chocolate, for example. But it includes one ingredient, grated raw sweet potato, that could potentially arouse skepticism. Without the word “surprise” appended to the recipe, home cooks might have passed on it.

“I really love old-school recipes,” says Danetra Richardson, owner of Swank Desserts, an online bakery based in Charleston. “I trust them a lot. I didn’t have to do much.”

Richardson was especially impressed with the shredded sweet potato — “I love desserts that have texture,” she says — and the use of both oil and egg whites. She deviated from the recipe as written only when making the frosting. To mimic the familiar flavors of the brown sugar topping on sweet potato casserole, she swapped out the coconut frosting for buttercream frosting with notes of cinnamon and caramel. The six-inch-tall cake is layered with the buttercream and marshmallow streusel.

“It was amazing,” she says. “I loved it.”