The present disclosure concerns a spot welding method, including the following steps of: arranging two electrically conductive parts to be assembled between two electrodes, each of the two parts having an interface zone between the two parts and a contact zone with one of the two electrodes; establishing a first electric current between the two electrodes through the two parts, the first electric current producing thermal energy capable of forming a weld nugget within the two parts; and adjusting a distribution of the thermal energy density produced by the first electric current based on the intrinsic characteristics of each of the two parts, to generate a weld nugget initiation zone at a selected depth in the parts to be assembled.