There are three beachfront restaurants attached to small resorts that are worth a mention and where you'll have a wonderful meal. Tides, adjacent the pretty pool and alfresco lounge at Water Lovers (tel. 073/579-0535; daily 12:30-2:30pm and 7:30-9:30pm), is one of my favorites, especially appealing for the fresh, healthful ingredients and focus on home-style cooking; the owners are Italian, so the small menu features Mediterranean-inspired dishes. The menu changes daily according to what's available and what's fresh -- the emphasis is on healthy, organic food -- and everything is scrupulously homemade. There are typically seafood, meat, and vegetarian choices, so lunch (15€) might be grilled fish skewers or risotto with pumpkin and parmesan, while for dinner (19€) you could get deep-fried crab claws followed by homemade brown-flour fettuccine with pesto and prawns. Reservations for mealtimes are essential and should probably be made a day ahead; you can also drop by during the day for snack, salads, and sandwiches (Ksh350-Ksh750). They serve great homemade ice cream here, too.
One of the busiest and best resort restaurants, with a lively lounge/bar atmosphere, is the Beach Bar (tel. 040/320-3643; daily 7am-11pm), which is literally right on the beach in front of The Sands at Nomad. The food is reliable, and there's a very large selection, including authentic-tasting pizzas and a lunchtime buffet (Ksh1,800). For an even breezier ambience, head to one of the slickest spots along the beach, Sails (tel. 020/213-8501; daily 10am-11pm or later) at Almanara, toward the southern end of Diani. It's a beachfront alfresco restaurant and bar with a handful of tables and cushioned armchairs under large canvas sailcloth, and some sea-facing sun loungers where you can sip premeal cocktails; it's wonderfully sociable, without the potential tackiness (and crowds) of the large resorts (and definitely the place to be if you're trying to get away from buffet tables). The menu -- which includes daily specials -- is perfect beach vacation fare. Fresh seafood is bought directly from the local fishermen, and salads and vegetables are grown in Almanara's own gardens at Villa Malaika. Salads are a mainstay here (try the octopus salad), best enjoyed with a serving of king fish or yellowfin tuna carpaccio, marinated with lemon juice and ginger. There's plenty of tasty comfort food, such as grilled rosemary chicken and thick-cut pepper steak, too.
If you're looking for a memorable experience, then what you really want is a private beach barbecue. Quite a number of fishermen in and around Diani will put on a fine spread for you, preparing straight-off-the-boat fish over the coals, but I suggest you contact Mohammed (tel. 072/620-4862); he and his team will set up an adorable makeshift dining area on the beach and treat you to a sumptuous meal for around Ksh1,500 per person (feel free to give something extra).
You'll hear about it frequently while you're in Diani, so it's worth warning you not to try Ali Barbour's Cave Restaurant, probably one of the most overhyped dining experiences in Kenya. What's marketed is the supposedly romantic thrill of feasting inside a genuine grotto, but reports of lackluster food (and, in some cases, illness) and the prospect of having to jostle for space with just about every other tourist in Diani makes this a wholly unsavory option.