Samir from The View From Fez blog has a great list of places to eat and sleep in Marrakech (as well as just about everything else anyone would ever want to know about Morocco). And the best Marrakesh restaurant guide I've ever run across is Footprint Guide's. But I want to stick my two cents in too. Everyone has a favorite spot for eating in Marrakesh. My friend Alisse, who had just gotten back before I left insisted that Yacout was THE place and Alisse is a great cook and knows food. Everyone says it's the most beautiful restaurant in town but the rap is that the food is... uneven, and even unpredictable. The idea of another huge overdone Moroccan feast was too much for me to handle and I never did experience it for myself.
Like I explained a few days ago when I wrote about eating in Fes, when I can I do my best to generally avoid the restaurants specifically catering to tourists. Occasionally one of these palace dining extravaganzas is done right-- and in Marrakesh, they have it down pretty well-- but most of the time these places are grotesquely over-priced and the food extremely bland and uninteresting to appeal to a lowest common denominator, taking elderly tourist bowel quirks more into consideration than authentic culinary excellence. The extreme, of course, is to pick one of the food stalls that cover an acre of in the Jemaa el Fna at night.
In the 35 or so years I've been visiting Marrakesh I think this was probably the first time I actually ate at a Jemaa el Fna food stall. I'm always so overly cautious about what I eat. I mean I don't even drink tap water in L.A. and I try as best I can to only eat organic food and never anything fried, and so on (nor do I eat anything made with sugar or flour or cooked in cheap oils). When I made my 2 year trip across Asia I noticed that my less picky friends, who ate as though they were born in places like Herat and Erzurum and Benares, were always coming down with seriously debilitating and revolting travelers' diseases like the infamous Kabul Runs (think Montezuma's Revenge on steroids). But the steaming bowl of harira Roland was slopping down greedily looked so good that I decided to go for it. There were no ill-effects and the harira was completely delicious (and only cost like 2.5 dirhams, as opposed to between 60 and 80 in the tourist restaurants, thirty times more!).
Anyway, let me share a couple of Marrakesh restaurant experiences with you. The only restaurant in Guéliz (the new city) we went to is the justifiably famous Al Fassia. The 2 unique things about it is that it is entirely run by women and that they revel in the concept of a la carte, never an easy thing for foreigners to find. The food was superb and expensive but not over the moon. And, like many Moroccan eateries, if you give them enough notice, they'll prepare things for you to order. The menu has all the best Moroccan standards and you can pick the ones you want and not have to bother with the ones you don't. It was sold out when we went and they said we'd have to come another time but begging and pleading helped and we were seated in an hour. I don't know if the dining room at the Riyad El Cadi takes non-residents (I don't see why they wouldn't if you asked politely) but the cooking is superb and, basically you tell them what you want in the morning and they serve it for dinner. You won't find better homemade type cooking anywhere. For our big night out the El Cadi's manager suggested we go to the Dar Zellij deep in the heart of the medina. I was intrigued because it isn't in any of the tourist guide books, although it is very much for tourists. We got there considerably before they were ready to serve so we spent some time talking with the very friendly and accommodating owner. The restaurant is simply one of the most beautiful I have ever seen. The food, although the typical tourist menu (unless you call in advance and order what you want, which we did), is PERFECTION. Everything was beyond delicious. And the servings were not gargantuan (as is typical in Morocco), although if you're a glutton, have no fear: they're happy to serve seconds on any dish you want more of.
Just a note about all the famous dives made famous by the hippies starting in the 60s that flank the Jemaa El Fna: the food won't kill you but if eating is a joy-- and in Morocco it should be-- these are not worthwhile places to waste a meal time. They basically all serve so-so completely unmemorable basics, neither good nor particularly bad.