The single greatest sandwich at any airport can be found at Tortas Frontera, at Chicago O’Hare (terminals 1, 3, and 5).
The only downside is that they make the sandwiches fresh, and while they’re generally ready in about 10 minutes I’ve turned up.. had to wait in line.. and been told to expect a 15 minute wait once I’ve been able to order. That can make things dicey on a quick connection – a choice between a delicious choriqueso and risking having to gate check a bag.
Now you no longer need to make that tradeoff…