If I had my way, I would eat mexican food every day for lunch (and most other meals as well). In reality, I'm not too far off from that pace, so I do try to find NEW mexican restaurants to somewhat appease @babymama. I was recently introduced to Sion's Mexican Restaurant in Manhattan which will help to diversify my mexican restaurant rotation.
The restaurant has a very small "diner" feel to it, with traditional sit-down service. As soon as we were seated, we were given the complimentary tortilla chips and salsa -- The salsa was quite ordinary, but the chips were very tasty and fresh. The menu had a standard mix of tacos and burritos, but the "Quesorrito" (or perhaps is was "Quesoburrito") immediately caught my eye. It was exactly what I would have expected by the name -- A loaded chicken burrito filled with melted cheese and golden-browned on the outside -- and it was delicious.
The prices were a little higher than I'd expect for the type of food, but not enough to prevent me from returning. I'm anxious to find what other treasures I can discover from their menu.