No, depending on the bottom of your microwave oven is what material, generally now the new microwave oven is made of ceramic material, can not be put directly, the cake is a flour will stick to the bottom of the hard to clean will also be to the bottom of the damage. You can go to buy some microwave special kitchen paper, put the cake on top of the paper. Or use a microwaveable glass bowl to bake in. Or use microwave-specific grill, grill pan and so on. If the glass tray of the microwave, dry the plate above, sweet potatoes can be put directly on the top of the heating, microwave heating speed, unnecessary to use the grill function, the cake because there is flour, oil and so on or need to be placed on a vessel, do not put directly on the tray.