if you are staying at the AKL, take the lodge tour, at the end of the tour they will take you down stairs where the a hostess will give descriptions of the offerings at Boma & then take you over to Jiko to sample some of their appetizers, they had 3 types of hummus to sample w/ pita & a "home made spicy cracker" style chip (the sun dried tomato hummus was wonderful, I've never tried hummus before because I didnt think it would be something I would like but ended up falling in love with it).
After the tour we stayed & talked with the guide a bit & he did say the menu at Jiko has more Americanized types of food, foods he didnt see in his country of Africa. A guest I spoke to the other day when I was there stated she ate at Jiko the night before & the food was way overpriced for the amount of food served. She order spring rolls that she said ended up being 2 spring rolls for something like 7 bucks. She said she was disappointed in her experience at Jiko, did not feel she received a value for what she paid for. I dont know if Jiko was the only restaurant you wanted to go to but we did Boma & I completely loved it. for 21.99 (including the non-alcoholic drink) you had many many things to choose from, alot of which is probably also served at Jiko. Boma also offers 14 or 16 (cant remember which) different desserts on the buffet in wonderful little "h'orderve" size portions so you can try several.
I skimmed the menu at Jiko and was not impressed. Please, please make PS's for Boma if you decide to go there instead because they were quite busy when we went for our PS's of 7:30.