Hi John, I'll suggest first to start with a pilot outlet project on your own, as a base and a reference to be able to sell it as a franchise on a bigger scale later on.
I have found that one tenet in marketing works rather well - Everyone wants what everyone wants!!
Simply put, build up traction for your product. Even if it means having to give it away virtually free to the first few smaller standalone restaurants and let them try it. You can iron out kinks, if any left over.
Once the big guys see something working, they will be more open to give you a hearing. To get a hearing, though, you will have to still invest in relationships with a local/regional heavy weight in that chain. It may not be some one who can take a decision, but definitely someone who can push your case upstairs.
There is just no shortcut to the process.