A gas burner assembly includes a first sheet, a second sheet, and a conduit. The first sheet has an inner face, an outer face, an upper portion, and a lower portion. The second sheet also has an inner face, an outer face, an upper portion and a lower portion. The first and second sheets are secured relative to one another such that the first and second sheets are separated by a gap that defines a manifold between the inner faces of the first and second sheets with an elongate opening between the upper portions of the first and second sheets, the opening forming an outlet from the manifold. The conduit is in communication with the manifold, the conduit being adapted for connection to a source of gas.