Students who hold minoritized identities are underrepresented in science, technology, engineering, and math (STEM) fields. Educational institutions often apply a deficit lens to understanding disproportionate outcomes between minoritized students and those from the cultural majority. Community Cultural Wealth (CCW) is an asset-based framework that focuses on the cultural strengths that diverse students develop in response to oppressive social structures, and which students use to be successful. Using a QuantCrit approach, we developed and collected evidence of validity for a measure of CCW. QuantCrit is a methodological framework that challenges researchers to critically evaluate their own biases to produce more equitable analyses. Each author reflected upon our experiences and the ways in which CCW manifested within our lived experiences. Through iterative reflection and discussion, we elected to design items that capture intersecting forms of CCW capital. We conducted cognitive interviews with minoritized students identifying with both seen and unseen forms of diversity to collect evidence of validity based on response process and to avoid construct underrepresentation. The resulting measure consists of 100 items on a 6-point response scale of agreement. Our methodological approach integrates teachings from critical theories to challenge deficit narratives and to capture the experiences of those frequently unheard by the majority culture.