The BCM89586M Scorpio3 Automotive Ethernet Switch Starter Recipe is a reference design intended to accelerate development of automotive Ethernet switch systems based on Broadcom's Scorpio3 switch architecture. It provides a validated hardware foundation covering power, clocking, reset, PHY connectivity, and management interfaces required for reliable in-vehicle networking. This starter recipe is optimized for automotive environments, addressing requirements such as EMI/EMC robustness, extended temperature operation, and deterministic low-latency switching. It supports modern vehicle network architectures, including domain- and zonal-based designs, enabling efficient aggregation and distribution of Ethernet traffic.