Hello, I love Mexican food and have a favorite place to eat at as well. However, I haven't had any treatment effects afterwards. I'm guessing the tortilla chips may have done it for you since they carry a large amounts of fat. Sometimes even a small amount of something you haven't had in a while will cause effects, especially if there is a higher fat content.
I don't eat the chips and any dish I like that has a corn shell, I ask to substitute with a flour shell. If you have the starter pack, check the "Healthy Eating Guide" or "Companion Guide" for eating out suggestions. There is a section in both books on Mexican foods.
Good luck and congratulations on continued success!
LaDonté