We had a fabulous time in London AND we were able to eat gluten-free, unlike in Paris. Here is a list (with pictures!!) of some of the gluten-free food my husband ate and whether or not we would recommend these places.
1. Wahaca - If you like good Mexican food (yes, Mexican food in England), then you'll like Wahaca. The food was very good, especially the grilled corn with a chili-sugar-mayo spread on it and the chicken taquitos. My husband liked the chicken caesar salad tostadas the best. The service was good, too, with a very friendly and helpful waiter.
2. Pizza Express - We actually ate at Pizza Express twice during our stay in London. Yes, we enjoyed it! I had a chicken caesar salad when we ate there the first time for lunch, but then we both got pizza when we ate there again (at a different location, though) for dinner. It seems like these places are ALL OVER London, so you're sure to run across one while you're out sightseeing. It bills itself as a family friendly restaurant, so it's good for the kiddos.
3. Cotto - While I REALLY enjoyed my regular pasta formaggio, my husband was not wild about the gluten-free pasta offered at Cotto. He said it tasted like the pasta hadn't been cooked long enough. The service was also not very good. It took forever to get the check, and the two hostesses just stood around and chatted with each other. There was another couple sitting next to us who were ordering gluten-free, too, and they seemed like locals, so I guess they like the place.
4. Snog - We are kind of obsessed with fro-yo, and so for lunch one day, we hit up Snog. They have gluten-free cones and brownies! My husband didn't get a cone or brownie, though. He went, as he always does, for the healthy stuff like fruit. I piled my fro-yo with chocolate!
5. Honest Burgers - This was my husband's favorite place we ate in London! We are always down for a good burger, and the fries here were really good! Good service, too!
6. The Truscott Arms - If you're looking for a gluten-free pub experience, you can find it at The Truscott Arms. We went there during lunch, and it was pretty empty, but I bet it gets crowded when the after-work crowd swings in. I had the traditional fish and chips, but my husband got another gluten-free burger!
So as you can see, it's very easy to eat gluten-free while in London. I can add that to my list of MANY reasons why London is one of my all-time favorite international cities.
Oh, and we also found gluten-free food at Tesco!!