Stewart made history by becoming the first female to win the cup since former America's Cup skipper Leslie Egnot in 1979.
The 15-year-old from the North Shore said it was unbelievable to have won such a prestigious competition.
"It is pretty mind-blowing actually. It is a tough event because four days definitely plays a part in tiring you out so it comes down to who doesn't lose it."
Stewart came second behind Keon in the final race by half a boat length which was enough to keep her slender lead and win the regatta.
She trailed both Keon and Rippey at the bottom mark and admits she was worried they might get away on her.
"That was definitely stressful and around the top mark I was quite a far way behind them but managed to crawl my way back slowly on the downwind.
Stewart loved sailing on the Tauranga Harbour and says it is just about the perfect place to sail.