What's in the new 'top-secret' Krabby Patty sauce? Wendy's keeping recipe 'closely guarded'

Wendy's is launching a new cheeseburger, the "Krabby Patty Kollab," inspired by "SpongeBob" with a top-secret sauce. They are also introducing a Pineapple Under the Sea Frosty. These menu items will be available in the U.S.