Rapid detection of pathogens present on contaminated surfaces is crucial for food safety and public health due to the high morbidity and mortality of bacterial infections. Herein, a sensitive and efficient method for on-site identification of foodborne pathogens on anisotropic surfaces was developed by using an in situ instantaneously prepared surface-enhanced Raman scattering (SERS) platform. To achieve this, molybdenum-doped gallic acid-derived carbon dots (MCDs) are utilized as the reductant for synthesizing Au@MCDs nanohybrids within just 3 s at ambient temperature. The synergistic effect of the electromagnetic enhancement and charge transfer of Au@MCDs enables excellent SERS performance 10 times stronger than bare Au NPs. The bioassay platform requires less than 5 min to complete the quantitative detection of foodborne pathogens on various microbial-contaminated interfaces with a sensitivity of 10 CFU/mL. This innovative strategy breaks the long-standing limitations of SERS substrates in practical use, such as the time-consuming process, interference of residual surfactants, poor surface stability, and few application scenarios, providing a promising tool for widespread applications in biomedical research and clinical diagnostics.