It's two pieces of bread, a piece of chicken, dill pickles and a squirt of mayo.
People have been eating chicken sandwiches ever since they've been eating poultry and bread, said Psyche Williams-Forson, an associate professor and chair of the Department of American Studies at University of Maryland College Park.
So how did this simple sandwich set off a national food fight this summer?
In fast food, Chick-fil-A has long dominated the chicken sandwich. It's part of what helped it become the third-biggest fast food chain in the United States — despite being closed on Sundays, according to Nation's Restaurant News.
In August 2019, Popeyes Louisiana Kitchen launched a chicken sandwich with pickles and a buttered bun. The sandwich was a huge hit — and other chicken chains took notice. Chick-fil-A teased its competitor in a tweet, saying its chicken sandwich was the original.
Popeyes' had a simple, but pointed response to Chick-fil-A: "Y'all good?"
"This is what people love to see," said Robert Byrne, senior manager of Consumer Insights at Technomic. "This is the reality TV series happening in real time with real companies and real dollars and real delicious food at stake."
Popeyes sold out of its sandwich in about two weeks. The sandwich's popularity raised Popeyes' profile with consumers — its Twitter followers nearly doubled during the two weeks it offered the sandwich, according to KeyBanc Equity Research Analyst Eric Gonzalez. Popeyes received over $65.1 million in equivalent advertising value from media mentions between Aug. 12 and 27, according to Apex Marketing Group estimates.
Chick-fil-A's rapid rise to the top has spooked competitors, including McDonald's, whose U.S. franchisees asked corporate to develop it's own competing chicken sandwich in July. By December, they got what they asked for. McDonald's started testing a Crispy Chicken Sandwich in two markets, entering the chicken sandwich wars.
So why is the chicken sandwich in focus right now? For decades, hamburgers have been Americans' sandwich of choice on fast food menus. Burgers are still No. 1, despite the recent interest in chicken sandwiches.
"There are big established behaviors in American food and beverage consumption, like eating hamburgers, whether or not the hamburger is the trendy category of the moment," said David Portalatin, vice president and food industry advisor for The NPD Group.
However, chicken sandwiches are gaining ground with consumers faster than burgers are, according to market research firm The NPD Group.
For the year ended February 2019, 4 billion chicken sandwich servings were ordered at U.S. restaurants versus 8.6 billion burgers, according to The NPD Group. Chicken sandwich orders were up 4%, while burger sales remained flat.
Who's winning the chicken sandwich war? Watch the video above to find out how the biggest chicken chains compare.