Generative artificial intelligence (GenAI) tools are increasingly adopted in education, yet many educators lack structured guidance on responsible and context sensitive prompt engineering, particularly in African and other resource constrained settings. This case report documents a three day online professional development programme organised by Generative AI for Education and Research in Africa (GenAI-ERA), designed to strengthen educators and researchers capacity to apply prompt engineering ethically for academic writing, teaching, and research. The programme engaged 468 participants across multiple African countries, including university educators, postgraduate students, and researchers. The training followed a scaffolded progression from foundational prompt design to applied and ethical strategies, including persona guided interactions. Data sources comprised registration surveys, webinar interaction records, facilitator observations, and session transcripts, analysed using descriptive statistics and computationally supported qualitative techniques. Findings indicate that participants increasingly conceptualised prompt engineering as a form of AI literacy requiring ethical awareness, contextual sensitivity, and pedagogical judgement rather than technical skill alone. The case highlights persistent challenges related to access, locally relevant training materials, and institutional support. The report recommends sustained professional development and the integration of prompt literacy into curricula to support responsible GenAI use in African education systems.