Burners and methods of making burner bodies via a focused beam are disclosed. In an aspect, a burner includes (a) a burner body and (b) at least one connector configured to supply at least a fuel and an oxidizer to the burner body. The burner body includes (1) a plurality of passageways; (2) a first major surface; (3) a plurality of ports at the first major surface, each port defined by an end of one of the passageways; and either: (4a) at least one heating element in or adjacent to at least one of the plurality of passageways that increases the temperature of a wall of the at least one of the plurality of passageways; or (4b) a cooling chamber directly adjacent to three or more of the plurality of passageways. The burner body includes a number of layers of metal directly bonded to each other. Further, methods are provided, including receiving, by a manufacturing device having one or more processors, a digital object comprising data specifying a burner body; and generating, with the manufacturing device by an additive manufacturing process, the burner body based on the digital object. A system is also provided, including a display that displays a 3D model of a burner body; and one or more processors that, in response to the 3D model selected by a user, cause a 3D printer to create a physical object of the burner body.