We describe a series of experiments to learn how to produce flat LaSrMnO3/YSZ/NiO-YSZ multilayer packages typically used for solid oxide fuel cells, in a single cosintering cycle, by applying a load during cosintering using sintering arches. We demonstrate that the key step is to apply the load gradually after the multilayer components are stronger and at their minimum viscosity of similar to 6 GPa.s during sintering. Alumina sintering arches, which support an alumina loading plate above the multilayer laminate, were designed to yield slowly at the intermediate stage of cosintering and thus apply the loading plate to the multilayer package. The primary design features of sintering arches are the arch material viscosity behavior, and the arch width, thickness, and curvature.