Chadwick moved through the field well before taking advantage of a 10-second jump start penalty for rival Pavan Ravishankar to take her first win.
Speaking after the race, the 20-year-old said:
Floersch released from hospital after horror crash
Today shows it's possible [to win] and nothing to do with my gender.
Brands Hatch was just the second round of the season, with Chadwick claiming a podium spot on the opening weekend at Oulton Park. And the youngster from Bath is confident that she can continue to compete at the sharp end for the rest of the season, telling reporters:
When I'm on the money I know I can be the quickest or one of the quickest.
F3 driver Floersch vows to return after horror crash