Large lecture classes in higher education continue to be a context in which large performance differences between underrepresented minorities and their White and Asian peers are observed. In the current study, we sought to develop a package of interventions that may reduce this gap in a multi-section Micro Economics course. The focus of this intervention was to re-design instruction in students' recitation sections, while also iteratively training teaching assistants on their instruction during recitation sections. Participants (N = 2,679) who were enrolled in Micro Economics worked together in groups where teaching assistants facilitated their learning in their recitation section. Results indicated that while all students demonstrated higher Micro Economics grades after the course transformation than their peers in prior semesters, this was particularly the case for underrepresented minorities, essentially eliminating the performance gap observed in prior semesters. Findings highlight the importance of instructional training for teaching assistants and employing teaching practices that can promote engagement and potentially promote inclusion during the learning process.