The Hollywood Athletics Club runner produced a breakthrough performance in Cape Town, beating three-time series champion Glenrose Xaba by five seconds to secure her first victory in the prestigious series.
Now, the 25-year-old heads into the second leg full of confidence after also winning the KwaZulu-Natal Athletics Championships and the Athletics South Africa Senior Track and Field Championships earlier this season.
Speaking to SABC Sport, Kavanagh said racing on the Durban course always gives her extra motivation because of the incredible support she receives from family, friends and local fans.
"I always enjoy running in the Spar ladies' series, especially the Durban route because that's where I call home. I always get amazing support there, and my family and friends come out in big numbers to cheer me on," said Kavanagh.
Kavanagh has never won the overall Grand Prix title, but she has put herself in a strong position after taking an early lead in the standings.
With races still to come in Gqeberha, Tshwane and Johannesburg, consistency will be crucial if she hopes to secure the overall crown.
The series winner will pocket R210,000 in prize money, along with additional bonuses for the top five South African athletes and a brand-new car at the end of the competition for a period of twelve months.
She is also expecting a tougher challenge in Durban, with a couple of Ethiopian runners set to return after missing the Cape Town race because of travel documentation issues.
Despite the stronger field, Kavanagh is embracing the challenge.
"I love seeing so many women of all ages taking part, and it's great that the Durban race is sold out. I enjoy the competition and always want to see what I'm capable of. I've been preparing well and working hard, so hopefully I can get another win," she said.