You’ll get this on the way to
But if you’re looking to just get this trophy in the fastest way possible, go to Freeplay > Custom > Create Championship > Add Event > Silverstone England and use the following settings:
Format: Full Format
Vehicle Class: RX Supercars
Weather: Whatever you want
Heat Laps: 2
Semi Final Laps: 2
Final Laps: 2
Then just complete all 6 short races and the trophy is yours.