In California, multilingual (ML) teachers seeking Bilingual Authorization or ongoing professional development must confront the field's sedimentary tensions. Cultivating culturally sustaining approaches to language learning in PreK-12 school communities requires embedding humanizing practices at the core of ML teacher education and professional development. Project MEDALLA (Multilingual Educator Development Advancing Language Learning Achievement/Activism) is based at a Hispanic-Serving Institution in Los Angeles. This article delineates MEDALLA's unique approach to bilingual teacher education, which fosters biliteracy and critical family-school relations while generating networks of educators committed to transformation. Informed by critical frameworks that unabashedly commit to sustaining students' and families' identities/knowledge and to thwarting oppressive ideologies, we describe how MEDALLA provides pathways to Bilingual Authorization and structured professional development for pre- and in-service teachers of color. The project's innovative methods include conducting grant activities in Spanish (the partner language), integrating critical bilingual family literacy, developing a year-long Plurilingüe Teacher Fellowship for mentor teachers, creating a holistic student teaching model, and strengthening partnerships. We believe that Project MEDALLA provides a model for supporting teachers' critical practices that advance students' and families' language and academic goals while building solidarity.