Over 1/3rd of the world population relies on fuel wood and biomass for their daily cooking needs with daily fuel wood requirement per person estimated at 1.3 kg. The use of solar energy would help in reducing the daily recurring burning of fuel wood, which would reduce deforestation, environmental and other ecological degradations. This paper presents test results and cost assessment of a new improved solar cooker designed for application in the developing countries. The newly developed cooker has been evaluated according to the two standard Figures of Merits (F1) and (F2), through; temperature stagnation and water boiling tests respectively. Sample cooking tests have been conducted using simulated solar radiation and the results have shown that the cooking requirements could be achieved. Comparative performance tests of painted and unpainted cooking pots had been undertaken and the results show that painted cooking pot achieves about 20% more heat compared to the unpainted cooking pot. The economic and environmental assessment of the system has also been performed. Using the cooker once a day could bring an annual savings of up to 1,281.2 Mtons and 114.2 Mtons of fuel wood and CO2 respectively.