The invention relates to a method for producing an assembly (1), in particular a power electronics unit, comprising the following steps: providing a component (2) to be cooled having a first surface (4), providing a cooling device (3) having a second surface (5) opposite the first surface (4), arranging a 3-dimensional heat transfer plate (6) between the two surfaces (4, 5), wherein the heat transfer plate (6) extends in a plate plane (11) parallel to the two surfaces (4, 5) and in the initial state a plurality of contact extensions (9) which extend outwards with respect to said plate plane (11), and bracing the component (2) and the cooling device (3) relative to one another, such that the contact extensions (9) are deformed in the direction of the metal sheet.