Pressure cooker gasket having a flexible skirt provided with notches

A sealing gasket for a cooking utensil for cooking food under pressure, said utensil comprising a vessel and a lid designed to be mounted on said vessel to define a cooking enclosure, said gasket being designed to be interposed between the lid and the vessel in order to seal said cooking enclosure, said gasket having a heel from which at least a first lip projects, said gasket being characterized in that the first lip is provided with at least one escape window notch that passes through its thickness, and in that said first lip forms a differential movement member designed to enable the escape window notch to effect a relative movement relative to the heel when the pressure prevailing inside the cooking enclosure exceeds a predetermined threshold, said relative movement enabling said escape window notch to open up a leakage orifice via which the cooking enclosure is put into communication with the outside of the utensil.