Season chicken with salt.
Heat oil in skillet on a high heat then carefully place chicken pieces in skillet.
Brown both sides and then transfer to a sauté pan and set aside.
Return skillet to a medium heat then add garlic and sauté.
Once garlic is a little golden, add chicken stock and five spice powder and stir making sure to lift the bits stuck to the skillet.
Stir until ingredients are heated through then pour on top of chicken and place sauté pan on a low heat.
Add chilies and and white parts of the scallions and combine ingredients before placing cover on pan.
Allow to cook slowly for 45 mins, checking regularly to ensure the sauce doesn't dry out.
If needed add 1/4 cup of stock or water to replace liquids that may have dried out.
Dissolve cornstarch in hot water, then slowly pour over chicken.
Move the chicken around to allow the cornstarch to mix with the rest of the ingredients, and then thicken the sauce.
Cover and allow to simmer for a further 15 mins to finish off.
When ready to serve, rip Thai basil up and then mix with green parts of scallions and sprinkle over each serving of chicken.