You've heard of people who combine different sandwiches from a fast food restaurant to create unique versions of the company's products. Now, you can combine ingredients from two different places to create an even more unique hamburger.

Strangely, the idea for this hybrid hamburger came from Burger King who challenged competitor McDonald's to combine the Big Mac with a Whopper for International Day of Peace.

The Whopper folks even came up with a specific place, uniforms and packaging so the two companies could join together to build the McWhopper.

McDonald's politely declined the offer.

However, you can still build your own McWhopper which combines six ingredients from each of the company's two popular burgers.

From the Big Mac, you'll need the top bun, one all beef patty, cheese, lettuce, special sauce and the middle bun.

From the Whopper, use the tomato, onion, ketchup pickles flame grilled patty and the bottom bun.

Assemble these into one giant burger that could either be a great combination or an equally giant case of heartburn. Oh yeah, happy Burger Day.