Introduction This study describes an innovative community-based participatory research model that engages community health workers/promotoras as research partners to address health inequities among Latinx and Indigenous Mexican immigrant communities during the COVID-19 pandemic.Methods Using ethnographic and qualitative research methods, we collaborated with promotoras trained in qualitative data collection and analysis to conduct seven focus groups (six in Spanish, one in Pur & eacute;pecha) with 55 participants in a rural desert region of Inland Southern California. Rapid analytic techniques were applied to identify emergent themes across data sources.Results Findings revealed deep-seated mistrust of institutions in the United States, including government, healthcare, and public health, fueling fear and suspicion around COVID-19 testing and vaccination. Promotoras bridged communities and institutions through their dual roles in public health response (contact tracing, testing and vaccination clinics, and health education) and participatory research (data collection, analysis, dissemination).Discussion This capacity-building approach positioned promotoras as trusted leaders such as science and public health education, demonstrating that engaging promotoras as co-researchers can strengthen institutional trust, enhance community participation, and advance health equity.