This chapter is grounded in research by two mathematics teacher educators (MTEs) as they teach courses in culturally relevant pedagogy (CRP) in mathematics to prospective and practising teachers (PTs). As both scholars are emerging “learners” in the context of teaching CRP courses, the chapter adopts critical lenses to study MTE self-understanding and professional growth. Data were gathered through PT projects and reflections on course content during offerings of courses in CRP in two institutions. Through personal narratives and conversation excerpts, the chapter situates the learning of two MTEs as they struggle with, and learn from, dilemmas and tensions in their teaching, including who and what is “relevant”, how do PTs respond to CRP in mathematics, and how might MTEs critically reflect on their own culturally responsive practices. Thus, this chapter focuses on the theme of learning and developing as a MTE, with a layer of emphasis on the role that PTs play in MTE learning when dominant mathematics discourses are disrupted.