Two weeks after McDonald’s rejected Burger King’s cross-marketing olive branch offer to put aside their metaphorical beef in the name of peace and create a burger marrying the two fast food chains, the King has decided to officially move forward with offers of collaboration from Denny’s, Wayback Burger, Krystal and Giraffas, unveiling a mismashed sandwich that includes bacon, ham, a square patty, egg, cheese and other ingredients.

Burger King announced Wednesday that the five companies will come together to offer 1,500 free Peace Burgers made with one key ingredient from each of their signature sandwiches from 11 a.m. to 6 p.m. on Peace Day – Sept. 21 – at a pop-up store in Atlanta.

A photo of the upcoming burger collaboration shows the sandwich will include ingredients from Denny’s Bacon Slamburger, Wayback’s Wayback Classic, Krystal’s Cheese Krystal, Giraffas’ Brutus and Burger King’s Whopper sandwiches.

In addition to adding to the special limited-edition burger, each of the restaurants participating in the collaboration will donate funds to Peace Day One, a nonprofit organization devoted to raising awareness and encouraging action on Peace Day.

The debut of the Peace Day burger comes nearly three weeks after Burger King first proposed the idea to create a McWhopper with McDonald’s.

The Golden Arches unceremoniously shot down the offer, leading to an onslaught of other chains stepping up.

“Since the beginning, the main objective of this initiative was to raise awareness of Peace Day,” Fernando Machado, senior vice president for global brand management at Burger King, tells Bloomberg. “We were overwhelmed by the goodwill of our fellow restaurateurs, and believe that working with them to create this once-in-a-lifetime burger is a beautiful twist of fate.”

[via Bloomberg]

Want more consumer news? Visit our parent organization, Consumer Reports, for the latest on scams, recalls, and other consumer issues.