Solar cooking is considered one of the most attractive ways to utilize solar energy. Therefore, in this work a high concentration ratio (11.12) solar box cooker prototype was manufactured and tested. The cooker has a cooking chamber with a glass cover on the top and is composed by two rows of booster mirrors. The prototype allows both an azimuthal and zenithal manual orientation. A test bench used to characterize the cooker performance is then described. Experimental tests without load were carried out to evaluate the maximum cooker temperature. Tests with load, conducted using aluminum vessels containing a certain amount of water, were accomplished with both standard vessels and black ones, and with one or two vessels. Additional tests were carried out with peanut oil. Using this fluid, temperatures higher than the water ones were achieved (>200 degrees C). Results show that the cooker is able to cook at high temperature with good optical efficiency and thermal insulation. (C) 2017 Elsevier Ltd. All rights reserved.