A method for joining together metal workpiece (12,14 or 12,150, 14) includes forming a laser weld joint (66) in a workpiece stack-up (10) that fusion welds two or more overlapping metal workpiece (12,14 or 12,150 or 14) together. The laser weld joint (66) has an initial top surface (76). Once the laser weld joint (66) is formed, the method calls for impinging the laser weld joint (66) with a laser beam (24) and moving the laser beam (24) along the initial joint (66) including the initial top surface (76). The laser beam (24) is eventually removed from the laser weld joint (66) to allow the melted upper portion (78) of the joint (66) to resolidify and provide the laser weld joint (66) with a modified top surface (84) that is smoother than the initial top surface (76). By providing the laser weld joint with a smoother modified top surface, residual stress concentration points are removed and the laser weld joint is less liable to damage seal strips.