Grease an oven tray with oil (I recommend the tray to be Teflon, because they stick a bit to the standard ones, not bad but it can deform the burgers). Form the burgers, or with your hands, in the shape of parjoale or with a special kitchen ring. Put them in the pan and put them in a preheated oven, about 180-200 degrees, medium heat in a gas oven.