The chile was most likely was brought over to West Africa from Portugal in the 15th century. The African populations at that time readily accepted the new chile, as they were already familiar with hot spices. Cubeb pepper, grains of paradise, and Ashanti pepper were regularly used in West Africa cooking.
Prior to the arrival of the Portuguese in West Africa, there is very little mention of spices in the diets of medieval Arabic people in this region. There is mention, however, of a “Sudan pepper” in Morocco. This was probably Ashanti pepper or cubeb, a variety of pepper known for its hotness. Ashanti was cultivated in places on the Guinea coast before the Portuguese arrival. There is also evidence that some spices were imported from North Africa, as told by Arabic travellers in the 16th century.
In today’s West African society, you will find the spiciest food of anywhere else in Continent of Africa. East, Southern, and Central Africa have mostly bland cooking in comparison, with the exception of Cameroon, Gabon, and the Congos. Some say these regions have even hotter food than in the West African region. There are also areas of Angola in the southwest part of the continent, and Mozambique in the southeast that are spicy areas. Portuguese colonies have brought that influence to those locations.
Spicy West African cooking refers to the cooking of Gambia, Guinea, Guinea-Bissou,Senegal, Mali, Liberia, Ivory Coast, Siera Leone, Ghana,Togo, Nigeria, Benin, and Burkina Faso. Oddly enough, in the southern parts of all of these countries, the food is hotter than the northern parts.
Western African food is dominated by various kinds of stews. And since breads are rarely found in West African cooking, the starches that are found are usually in the stews. Typically, you will find millet and sorghum as the dominant grains in West Africa. You will also find rice, wheat, and beans in the West African diet, but to a lesser extent.
Another important food of West Africa is a cereal called fonia, which is fairly bland, but easily cultivated. It does well in times of drought, so therefore has a very important role in the food of West Africa. Wheat is rare and expensive, so it plays a minor role in the diet of West Africans.
And as to the importance of cooking fats in West Africa cooking, red palm and peanut oil are essential fats since the discovery of the New World.