Abstract: A container that is filled with a product through an open end and which is suitable for use in a microwave or conventional oven to hold the product while it is heated. The container is formed of a paperboard blank coated with polyethylene (microwavable) or polyester (microwavable and ovenable), and is folded, filled and thermally sealed on a slightly modified, but generally conventional machine that is otherwise used to assemble and fill prior art end filled containers. The blank includes a first panel having two end walls, front and rear sidewalls, and four gusset corners, and a second panel connected to the rear sidewall along a fold line having two end flaps, and a front flap. A tear-open access flap is defined on the second panel by partially die cut lines. In a first embodiment, the first panel is imprinted with graphics and the second panel with cooking instructions.