Guinea-Bissau's cuisine is West African at heart with a strong Portuguese influence. Rice is the foundation of almost every meal along the coast, while millet and sorghum are more common in the interior.
Caldo de mancarra is the closest thing to a national dish: a rich, hearty stew of shrimp and ground peanuts, served over rice. You will find it everywhere, from street stalls to the few restaurants in Bissau. It is simple, filling, and delicious.
Fish and seafood dominate the coastal diet. Grilled fish served with rice and a spicy sauce is the everyday meal for much of the population. The waters off Guinea-Bissau are exceptionally rich -- barracuda, grouper, shrimp, and crab are all common. On the Bijagos Islands, fresh-caught fish grilled on the beach is as good as eating gets.
Jollof rice appears here as it does across West Africa, cooked with tomato paste, palm oil, onions, and whatever meat or fish is available. Calulu, a fish stew with okra and palm oil, is another staple. Yassa chicken -- marinated in lemon and onion, then grilled or slow-cooked -- shows the Senegalese influence on the cuisine.
Cashew nuts are everywhere during harvest season (March to June) and are often roasted and sold by the roadside. Cashew wine, fermented from the fruit of the cashew tree, is the local drink of choice in rural areas -- it is sharp, mildly alcoholic, and an acquired taste. Palm wine is also widely consumed.
Fresh tropical fruit is abundant: mangoes, papayas, bananas, and citrus. Street food options in Bissau include grilled meat skewers, fried fish, and simple rice dishes.
Don't expect much variety in restaurants. Outside Bissau, your options are essentially whatever the local cook has prepared that day, which is usually rice with fish or chicken in sauce. Embrace it.