Pedagogical Content Knowledge (PCK) observed in one topic is commonly understood not to be transferable to another topic. This study asked, what can then be transferred in the context of learning and acquiring PCK? The study firstly posits the existence of a generic pedagogical competence that is developed in pre-service teachers to pedagogically transform content knowledge, thereby developing their PCK exclusively in the topic, distinguished from general PCK as Topic Specific PCK (TSPCK). It then investigated the transferability of the competence learnt through an intervention on particulate nature of matter for the development of TSPCK in a subsequent, much harder topic chemical equilibrium. The location of the study was in a chemistry methodology class with 36 pre-service teachers. Mixed methods were employed in the research design. The intervention focused on developing the competence to transform concepts in the topic of particulate nature of matter. The primary data comprised a set of completed pre- and post-TSPCK tests in both topics, measuring the extent of the shifts in the quality of the construct. Additional qualitative data in the topic of the intervention was collected from class activities and Content Representations (CoRes) during the intervention, while a vignette was used in the second topic. The findings show the success of the intervention in enabling pedagogical transformation of the content knowledge in both topics, thus demonstrating a successful transfer of the learnt competence. Implications for the development of PCK in core topics in a discipline through transfer of the pedagogical transformation competence are provided.