There are allegedly 65,000 combinations of Chipotle ingredients, and longtime managers have had most of them
A manager is required to taste-test for food quality assurance all day long (sucks to be them), so it becomes habit to start creating different combinations. Mathematically, when you consider everything there is to combine, it works out to 65,000, ranging from "just a plain tortilla" to "every single thing in the restaurant."
Obviously, some are better than others. Caldarone -- who claims to have tried almost every possible ingredient permutation -- says the best combination is corn tortilla steak tacos with peppers and onions, hot salsa, sour cream, cheese, and lettuce.