Abstract: The invention relates to a method and device for carrying out the automated preparation of foodstuffs by portions, especially french fries made of potato sticks or the like that are previously fried in oil, by baking them inside an oven cavity (15). The oven cavity (15) is surrounded by a casing (1) which is provided with a bar code reader (9) that is connected to a control (44). Said control enables or refuses the actuation of the device according to the information contained in the bar code that has been read, and/or controls the baking time and/or the baking temperature and/or a preheating temperature.