Heat the olive oil in a large pot on medium heat. Add in the diced onion, garlic and ginger and sauté for 5 minutes until the onion has softened.
Add in the curry paste, stir and let cook for 2 minutes before stirring in the broth, coconut milk, fish sauce, lime juice and shredded chicken.
Let the broth simmer for 5 minutes before adding in the zucchini noodles, scallions and half of the sliced red chilies. Let the zucchini cook in the broth for 1 minutes before removing from the heat (don't let them overcook and become mushy).
Divide between bowls and top with the remaining slices of red chilies and thai basil.