Aerospike engines are a promising type of rocket engine with the potential to significantly improve the efficiency of rocket propulsion systems. Unlike traditional bell-shaped engines, aerospikes have a cone-shaped external contour that allows for more efficient combustion of the propellant in a variety of environmental conditions. The design of aerospike engines presents a challenging task due to their complex internal and external geometries. However, the recent advancements in additive manufacturing (AM) have made it possible to create these complex shapes with greater accuracy and precision. This contribution addresses the complete process chain of an additively manufactured aerospike breadboard engine using kerosene and hydrogen peroxide as propellants. The aerospike was fabricated by laser powder bed fusion (LPBF) using the nickel-based superalloy INCONEL® 718. In order to qualify the material and process for this application, an extensive material characterization campaign including density and roughness measurements, tensile tests at room temperature, 700 °C and 900 °C, was conducted. In addition, various geometric features such as triangles, ellipses and circular shapes were generated to determine the maximum unsupported overhang and geometric accuracy. The results were taken into account in the design maturation of the manifold and the cooling channels of the aerospike breadboard engine. Postprocessing included heat treatment, milling, turning and eroding of interfaces, thermal barrier coating (TBC) of thermally stressed surfaces and laser welding of spike and shroud as well as quality assurance.