This invention is directed to a method for creating a triple layer like golf ball core out of a single material. A thermoset material is cured for only a partial period of time in a compression mold, therein creating a short-cured core wherein the innermost region of the core is substantially softer than the outer region. Subsequently, the short-cured core is heated with infrared radiation to create a cure gradient in the skin of the core. This results in a relatively hard skin, which is at least 2 Shore D points harder than the rest of the core. The hardness gradients created in the skin are in the range of about 0.005 inches to about 0.040 inches.