This tray of burgers was inspired by an old Denver chain called Rocky Bilt.

Long gone now, but I found a guy on YouTube that posted the sauce recipe:

Equal parts: sweet relish, Heinz 57, Yellow mustard. (I added a very small amount of mayo just so it sticks to the bun.). I’ll try to find the video.

No idea how close this is to the OG but it was a nice change up from the In-n-Out style spread.