Bay Curious is a podcast that answers your questions about the Bay Area. This story is part of a series on locally-invented foods inspired by a question from listener Brent Silver. It first aired on The California Report Magazine.

It’s hard to imagine in this era of salted caramel and matcha tea, but there was a time when the American ice cream palate was limited to chocolate, vanilla and strawberry. The invention of Rocky Road in the 1920s changed the ice cream game with “mix-ins” — adding the bumpy texture of nuts, and the soft, pillowy chew of marshmallows.

Nearly a century has passed since Rocky Road was invented, but there’s still a dispute over just who thought up the recipe for Rocky Road ice cream: Fenton’s Creamery or Dreyer’s Grand Ice Cream. The one certain thing is that the flavor was invented in Oakland, California.

An Antidote to the Great Depression

“There was a man named William Dreyer. He was a German immigrant. He loved making ice cream and so he made it out of a candy shop,” said Local Tour Adventures guide Lauren Herpich, whom I joined for an ice cream tour of College Avenue — a tiny shopping district running through North Oakland.

The street is home to the original headquarters of Dreyer’s Grand Ice Cream, which was founded in 1928.

A year after its opening, the American stock market crashed. Shantytowns consequently developed along Oakland’s waterfront.

“So William Dreyer decides ‘what I want to do is make a new ice cream flavor that puts a smile on people's faces during this rocky road of life,” Herpich said. “Rocky Road becomes America’s first blockbuster ice cream flavor after chocolate, vanilla and strawberry. So really, we can say thanks to Mr. Dreyer for starting the whole idea of new ice cream flavors.”

That is the official story from Dreyer’s, too.

“[It was] the first time marshmallow was ever used in ice cream,” said John Harrison, the guy who invented Cookies 'N Cream ice cream and some 75 other new flavors for Dreyer's starting in the 1980s. He was also part of an oral history project with UC Berkeley’s Bancroft Library, documenting the long history of Dreyer’s Grand Ice Cream in Oakland.

“The only marshmallow that was available in 1929 was the large fireside marshmallow that their wives used to cut up, bite-size. You can’t put a whole. Wouldn’t work,” Harrison explained, making gummy chewing sounds.

Harrison said William Dreyer adapted a popular candy of the period, made with marshmallows and walnuts — but he used almonds instead.

“The candy and ice cream industry has been interwoven since day one,” Harrison said. “Originally, it was walnuts, but it didn’t have that bite, that crispness, that freshness, lasting. It’s too porous. It absorbs and gets soggy."

Dreyer’s has expanded well beyond Oakland since. It was bought by Nestle in 2002 and its ice cream is stocked in nearly every supermarket freezer (It's branded as Edy’s on the East Coast.) Nestlé continues to market the brand and the claim that Dreyer invented Rocky Road.

Walnuts vs. Almonds

Just down the road from where Dreyer’s got its start in Oakland, there’s another much smaller ice cream company that also claims to have invented Rocky Road.

At Fenton’s Creamery, owner and master blender Scott Whidden holds a tub under a spigot churning out fresh chocolate ice cream. He puts in fistfuls of nuts and marshmallows that he scoops from plastic tubs. He adds walnuts, instead of almonds — just like the original candy bar.

“I'm looking for equal parts [in each bite],” explained Whidden over the whirring ice cream machine. “If you have a marshmallow, I want you to have maybe one or two of the walnuts,” he said.

Whidden said small-batch and handmade is the way Fenton’s has made its ice cream since the 1920s.

That, he said, is when Melvin Fenton — grandson of the original owner — came up with the idea for Rocky Road. There’s a picture of him in the parlor, where dozens of families are sitting in red vinyl booths enjoying giant sundaes in old-fashioned glass dishes. In the photo, Melvin Fenton is loading fresh cream off of a tiny airplane that he flew as an amateur pilot.

“Melvin was like the black sheep of the family,” said Whidden. More like a wildcat and an inventor who could see beyond the trifecta of vanilla, chocolate and strawberry.

“He’s a visionary,” said Whidden. “Forward-thinking guy. And he goes, 'Whoa. Mix-ins!' So the thought process on it was, we’re into the depression, it’s bad times. Smooth ice cream, and then there’s these bumps, it gets rocky.”

That sounds familiar: Rocky Road, the bumpy road of life during the Depression. Chocolate, marshmallows, nuts.

An Ice Cream Expert Weighs In

These days, Rocky Road is still one of Fenton’s top-selling flavors. They serve it up in giant scoops and decadent sundaes. When I visited Fenton's, Amy Ettinger and I ordered sundaes with whipped cream and cherries, gleefully fishing for the walnuts and marshmallows. Ettinger is an ice cream historian, the author of “Sweet Spot, An Ice Cream Binge Across America.”

“It's very common in ice cream history to have these kinds of disputes,” said Ettinger. “The 1904 World's Fair was when the ice cream cone was invented and six different vendors claimed that they were the ones who invented it. Unless you have a time machine, or you know you were actually the inventor, there's no way really to tell.”

Ettinger said Rocky Road is the flavor of her childhood. Not the Fenton's Rocky Road she's eating, but the Dreyer’s with the almonds you can buy at the grocery store. She said she feels a little sheepish saying that, because it’s kind of a David and Goliath story: the mom and pop parlor versus what is today a multinational giant.

“What's very interesting is Fenton's is a very beloved Bay Area institution,” said Ettinger. "But it is not well known outside of the Bay Area. So regardless of who actually invented it, Dreyer’s is hands down the marketer of Rocky Road. They built their brand on the invention and the marketing of Rocky Road. Just because the other company is the one that got the word out about it, doesn't mean that Fenton's didn't invent it. There's no way for us to know.”

There are other theories too:

Fenton’s original candy maker, George Farren, was friends with Dreyer and so perhaps he shared his idea for a Rocky Road ice cream based on the candy with both ice cream companies. It's unclear whether the original candy bar, popular in the 1920s, was called Rocky Road. There's still a Rocky Road candy bar today, invented in San Francisco in the 1950s, that uses cashews. It's all a bit nutty!

Fenton's owner Scott Whidden claimed Dreyer’s just stole the credit, even though they knew Fenton’s had invented it. Whidden said Dreyer’s former president Ken Cook, who ran Dreyer's from 1963-1977, was his mentor. The one who encouraged him to buy Fenton’s and admitted to him that Fenton's actually invented Rocky Road. Cook passed away in 1991, so there’s no way to verify that claim, although the online publication Quartzy tried to track it down.

Then there’s the even more radical theory that, in fact, Rocky Road was born in Topeka, Kansas. There is a recipe in a candy cookbook printed there that predates either Fenton’s or Dreyer’s. It calls for honey whip instead of marshmallows.

Ice cream expert Amy Ettinger said the Kansas theory doesn’t count because honey whip isn't marshmallows. Rocky Road definitely came from Oakland. And who cares who invented it?

"At the end of the day I don't know that it matters,” said Ettinger. I mean, if both places are creating really good scoops of Rocky Road ice cream now, and they both have their little twist on it. How important is it who the original inventor was?”