The year was 1967. A McDonald's franchise owner named Michael "Jim" Delligatti had an idea.

Competing fast food restaurants served double burger sandwiches. Shouldn't McDonald's? So, he came up with a recipe: two all-beef patties, special sauce, lettuce, cheese, pickles, onions, and a sesame seed bun.

If that sounds familiar, of course it's because Delligatti invented an icon: the Big Mac (which also led to an iconic McDonald's jingle).

McDonald's corporate didn't love the idea at first, but Delligatti tried it in his 48 McDonald's locations. Soon, it took off, to the point that McDonald's shared it in restaurants around the world.

For much of that time -- and especially in the last few years -- hardcore devotees of McDonald's have declared that there might be something missing from the Big Mac: a double-decker chicken version of the sandwich.

This week, fully 55 years after Delligatti introduced the original Big Mac, McDonald's fans got the news they've been waiting for -- or at least, a taste.

McDonald's USA confirmed to me Friday that it's testing a Chicken Big Mac for a limited time at select locations in the Miami area. Much like the original Big Mac, if things go well, you can imagine it quickly being shared at McDonald's restaurants across the country.

Here's the official McDonald's USA statement:

"We're always looking to give our fans more ways to enjoy the classic menu items they know and love. And starting later this month, at select Miami restaurants, we're testing a new twist on an old favorite: the Chicken Big Mac ...

"While not everything we test makes it on our U.S. menus, we'll use this time to gather feedback from both customers and restaurant crew as we consider opportunities to offer more delicious options in the future." 

Now, for longtime McDonald's watchers, the surprise isn't that McDonald's is testing a Chicken Big Mac; it's that it took so long to arrive.

Back in 2018, I wrote about leaked McDonald's documents that showed McDonald's had a plan -- the "Better Chicken" project -- about how the company hoped to become "a credible chicken player." (Doesn't that sound tasty?)

In fact, McDonald's has tested chicken all over the world in the past.

The Chicken Big Mac was already introduced for a limited time in the UK, where the company said it got "rave reviews," and McDonald's either offers it now or did offer it in Australia.

Also, while working on this story I did a bit of double take to find a "Chicken Mac" on the menu at McDonald's, looking exactly like a regular Big Mac with chicken -- only to realize that I'd stumbled onto the McDonald's webpage for its stores in the United Arab Emirates.

In fairness, changing the menu at McDonald's, even "just" the 13,000-plus restaurants in the United States alone, is a tricky affair. As an example, perhaps even more than people have clamored for a chicken version of the Big Mac, customers also asked McDonald's to start serving breakfast all day.

McDonald's eventually gave in, only to find that it was a terrible deal for McDonald's and its franchisees, because regular customers simply started coming in later -- and buying cheaper breakfast items later in the day.

But this time, if the early reaction to the McDonald's Chicken Big Mac is any indication, looks likely to be a hit.

Delligatti, who invented the Big Mac, died six years ago at the age of 98. Reportedly he ate at least one Big Mac per week for more than 50 years.

Look, as I write in my free ebook, What You Learn When You Work at McDonald's, it's hard to imagine a company that experiments more with its menu than McDonald's, and where tiny changes can have a massive effect on so many people.

No innovation, however, would mean total stagnation. And that's even worse.

Even if it takes more than half a century.