A package for microwave heating of food products includes a multi-layer sheet material having a first paper layer defining an exterior portion of the assembled package. A metallized polyester is laminated to the paper layer and defines the interior portion of the assembled package. A plurality of pinholes extend completely through the sheet material. Peripheral regions of the sheet material are left free of any pinholes to receive an adhesive for securing the sheet material to itself and form the completed package. Absence of the pinholes inhibits passage of the adhesive to the interior of the assembled package.