Microcredentials are increasingly recognised as flexible instruments for lifelong learning, yet their pedagogical design and educational effectiveness remain underexplored. This paper presents the development and initial evaluation of an Italian microcredential on formative feedback, created within the Erasmus+ Learning to Learn through MicroCredentials (L2L Microcred ref. 20241NO01KA220ADU000256871) project. Grounded in a learnercentred pedagogical toolbox codeveloped across four countries, the blendedlearning microcredential was designed to strengthen teachers’ assessment literacy by focusing on feedback as a communicative practice. The study involved 72 preservice and inservice primary teachers who completed reflective journals throughout the course. A thematic analysis of 288 reflections identified a progressive shift in participants’ understanding of feedback, from a corrective and summative practice towards a relational, formative, and learningoriented process. Participants demonstrated increased awareness of the emotional, motivational, and selfregulatory functions of feedback, as well as its role in informing instructional decisionmaking. The findings suggest that structured reflection on authentic classroom experiences and biographical learning can effectively foster teachers’ professional awareness of assessment. The study highlights the potential of welldesigned microcredentials to support meaningful professional development in teacher education while providing an empirically grounded model for designing learnercentred, transferable microcredentials.