We thought the lunch menu, as well as the prices, at Les Chefs de France was great this past June. We aren't big eaters and DH and I often share a meal, as do my children. We were able to have a very nice, light lunch for around $30 for a family of 4. DH and I shared the 3 course meal, it included soup, a small salad with a sandwich, and a dessert. My kids shared a kid's meal and we had lots of warm fresh bread before our meal and the kids shared a cookie after their meal. The food here was great, as was the service.
We also had a decent, light dinner at San Angel Inn. DH and I shared a bowl of soup, then ordered two appitizers to share. You can do soup, or salad, and appitizers just about anywhere.
Beaches N Cream is great, but I don't really recall anything on their menu being "light".