Abstract: A bag for popping popcorn in a microwave oven has substantially rectangular front and back face panels and gusseted side panels joining the opposite side edges thereof. Top and bottom ends of the bag are normally closed and sealed, but the top end may be opened to remove the contents of the bag. The gusseted side panels unfold during cooking to enlarge the interior volume of the bag, forming triangularly shaped corner flaps at the junctures of the side panels and the front and back panels, respectively. In conventional bags, the confronting surfaces between the triangularly shaped panels of the corner flaps move apart when the side panels unfold and the bag expands during cooking, forming pockets between the confronting surfaces in which food particles may become trapped. In the invention, spots of adhesive are placed between these confronting surfaces to hold them in contiguous relationship to one another and prevent the formation of pockets, thereby enhancing the yield of food cooked in the bag.