There is a distinct difference in the sauce used to make Big Boy's Slim Jim sandwich.. the Elias Brother's chain (in the midwest) uses tartar sauce, and Bob's Big Boys out west use a type of 1000-Island.. since moving from Michigan to Florida, I had to figure out how to duplicate that awesome sandwich, and I did it. The key is this tartar sauce, which is kind of silly, because how many ways can you make tartar sauce, lol.. Well one day when I was back in Michigan for a visit, I bought a jar of their famous tartar to bring home with me, and made a simple clone from the ingredients listed on the jar. This is perfect. Now I can have Slim Jims whenever.. Oh! Today was whenever - LOL!!