This study aims to inform teacher educators, professional development specialists, and researchers how they can better support teachers in designing blended PBL, especially in online environments. The study focused on an individual project, which required the participants to design a blended PBL lesson for their selected target audience. The results of this study suggest that professional development programs provide PBL novices with (a) an opportunity to design the whole PBL process using a systematic approach, (b) synchronous, interactive questioning sessions and customized scaffolding, (c) concise and easy-to-understand guidelines and checklists, and (d) opportunities to have a successful experience with PBL design.