Salt? You put it everywhere and in ancient times was literally used as “salary” for workers.
Hence the term “worth your salt”.
P.S. I just made that up, I have no idea if it’s true.
Mustard
Mayonnaise because it goes with everything. You can add flavour to mayonnaise. It’s the most versatile of the condiments.
Respectfully disagree. Mustard on a pretzel, yay! Mayo on a pretzel, yugh!
Mayonnaise.
It’s utilitarian as fuck and goes on or with everything. Think of every other condiment listed here and think what you usually use it on. Guarantee it’s also got mayo or even has mayo in the condiment.
Mayo and mustard are definitely what came to mind for me. And if the two, mayo is far more useful. Sandwiches of every kind, it’s the base for numerous spreads and dips, and it even goes great on stuff like sushi. You can mix it with so many things to make unique and interesting sauces. Eg, I use chipolte and garlic mayo for many sandwiches I make (and sandwich like things such as wraps). Sriracha mayo is a classic in sushi. It’s usually the basis of a good fry sauce.
BBQ sauce. Sweet baby rays if you are doing store bought.