Funny Business with Jane Wells

Big Mac vs. Big King: Watch our taste test

Wells: Big Mac vs. Big King

The burger world is #atwitter with the new "Big King" from Burger King, which looks like a flame-broiled copy of the famous Big Mac. Both have two all beef patties, special sauce, lettuce, cheese, pickles, onions on a sesame seed bun.

Except the Big King has fewer sesame seeds. And the patties taste like Whoppers. And the pieces of onion are larger.

Does that make it better?

First, a little history. The Big King is not new. Burger King debuted it several years ago in certain markets. Much like the McDonald's McRib, the Big King developed a fan base wishing for its permanent return. There's even a Facebook page dedicated to this, but if you look at the image of the burger on the page, you'll see the Big King is missing a middle bun.

That's now been remedied. As Burger King rolls out the Big King nationwide, it has added a middle bun, making the Big Mac homage, if you will, complete. When I showed fast food fans (and one vegetarian) a photo of the Big King, all of them thought it was a Big Mac. "I'd eat that," said one man (not the vegetarian).

I bought a Big King and a Big Mac and taste tested them both. That's the video here. While they look the same, they do not quite taste the same. The Big King tastes like a Big Mac but with a tastier patty, and if you like onions (I do), you will like the Big King better. After I finished my taste test, the cameraman—a certifiable health fanatic who melted in the face of his childhood comfort food—did a little taste testing himself.

"I've always been a McDonald's guy," he said afterwards. "Gotta stick with the Big Mac."

(Read more: Holy Big Mac! McDonald's tests out mobile payments)

That may remain Burger King's biggest dilemma. So many of us have "always" been McDonald's guys. Why buy a Big King when you can buy a Big Mac? The King is about 30 cents cheaper, but will McDonald's feel threatened by this latest Big Mac attack?

"We're focused on our business and our customers," a McDonald's spokesman told us. The company recently dropped Heinz from markets where it was still using the ketchup after the CEO of Burger King left to become the CEO of Heinz.

Nielsen tells us that Burger King spends about one-fourth of what McDonald's spends on advertising, and Burger King tells CNBC that it does not plan to air commercials for the Big King.

Instead, it's counting on PR stunts, like a report in TMZ this week that the company offered to buy Elvis Presley's home in Beverly Hills. Get it? The King? Burger King? While the company tells us the offer was legitimate, management couldn't have it their way.

The bid was reportedly rejected for being way too low, a mere $3.69 million.

That figure is no fluke. The Big King is selling for $3.69.

—By CNBC's Jane Wells; Follow her on Twitter: @janewells