A food or beverage container with a valve. The valve is defined by an aperture in the one of the base or cover, and a valve element including an elastic panel. The panel has a first section secured to the cover by an elastic mounting tab which extends through the cover and is secured thereto. The elastic panel has an undeformed position spaced from the aperture such that the valve open condition is the default condition. The panel may be manually moved to a deformed position to close the aperture by a plug. This plug may include a shaft having an enlarged head, with the elastic nature of the panel ensuring forced contact and creating the valve closed condition. The elastic nature of the panel is tuned to allow the plug to be drawn inward during under-pressure with the container. This inward movement will break contact of the enlarged head a valve vent condition. With the interior of the container so vented and under-pressure reduced, the elastic nature of the panel will again move the plug outward to the valve closed condition. In this way the valve may automatically regulate pressure within the container during cooling.