The present work concerns the modification of the grid of the Nansu stove, used in many households in Africa and in particular in Benin. The performance of the stove obtained (modified Nansu) was estimated and compared on the one hand with that of the corresponding reference stove and on the other hand with that of the ordinary Nansu stove. To do this, the Controlled Cooking Test (CCT) was used to determine the specific fuel consumption and cooking time for three dishes, namely rice, beans and voandzou. The results of these tests show that the modified Nansu fireplace is significantly more economical, in terms of fuel consumption and cooking time, compared to the ordinary Nansu fireplace. The savings made by the modified Nansu stove compared to the ordinary Nansu stove are 34.57% to 64.31% in specific consumption and 9.42% to 37.81% in cooking time depending on the type of dish.