In Texas, we love our Mexican food. Growing up in my family, Mexican food wasn't called Mexican food, it was just called food. We ate it all the time! Much to my disappointment, I learned that corn chips were definitely not on any of Doug's diets. A lot of the food I had grown up eating wasn't on Phase 1 or 2 because many Mexican dishes are loaded with corn, corn breading and rice. No queso, no chips, no sopapillas - I was really bummed out.
A lot of food prepared in Mexican fashion is great for Phase 1. Fajita chicken and beef with peppers is great. Guacamole made with onions, garlic, and lime is loaded with anti-fungal nutrients and all that good, healthy fat that you find in avocados.
Salsa can fall into a grey area. Salsa can be great for Phase 1; it can also disguise itself as healthy, but in reality be loaded with sugar and other unhealthy ingredients. Salsa's compatibility with Phase 1 dieting is totally contingent upon it's ingredients and how it is prepared. I personally have made some excellent Phase 1 salsa before simply with tomatoes, lime, lemon, onions, garlic, jalapenos, cliantro and bell peppers. I've made it raw or reduced it over low heat - either way is fine. If you are buying salsa from the store, be sure to check the ingredients list. If it has added corn syrup, sugar, corn, or chemical preservatives (many derived from corn), it probably isn't OK for the diet. Try making your own!
Tortillas are allowed on Phase 2, albeit very sparingly. Again, be sure to read the ingredients when buying tortillas; I've noticed some made with yeast derivatives. White or wheat probably doesn't matter since they should be eaten in such moderation.
Black beans are a legume and therefore OK for Phase 2 as well. Black beans are supposed to be one of the healthiest legumes available. They are loaded with protein, fiber, manganese, magnesium, tryptophan and a host of other nutrients. I've heard Doug recommend black beans to people who need some extra carbs in their diet or to vegetarians wanting to go on the Phase 1. Black beans are a great energy source that won't spike your blood sugar levels.