Course-based undergraduate research experiences (CUREs) have emerged as a promising approach to enhance undergraduate STEM education by engaging students in authentic discovery. CUREs integrate genuine research projects into undergraduate courses, providing students with a real research experience while earning academic credit. While CUREs offer similar benefits to traditional research experiences, they have the advantage of reaching a larger student population and being accessible to all enrolled students. In this study, we assess the outcomes of the first reported large-enrollment physics CURE within an introductory physics laboratory. One of the primary learning objectives of this CURE, which took place at the University of Colorado Boulder from 2020 to 2021, was to foster the development of more expertlike attitude and beliefs about experimental physics among the students. To evaluate the impact of the CURE along this dimension, we employed the Colorado Learning Attitudes about Science Survey for Experimental Physics (E-CLASS). Precourse and postcourse E-CLASS responses were collected from the CURE participants and compared with data from 363 other first-year physics labs, representing over 20 000 students. We found that students enrolled in the C-PhLARE CURE led to significantly higher scores on many of the E-CLASS items, even when controlling for precourse scores, students' majors, and students' genders. In particular, we observed that the C-PhLARE CURE had a significant effect on many of the E-CLASS items aligned with the objectives of the course; notably, students had more expertlike views in areas such as communicating scientific findings to peers, understandings of authentic research practices, and students' belief in their own research capabilities. Additionally, we found no statistically significant negative impacts on any of the E-CLASS items as compared to the effects of other first-year physics labs. These results demonstrate the efficacy of this CURE in impacting students' views of experimental physics.