Skin chicken and cut into 1.25 X 1 in strips. Remove stems from chilies and cut lengthwise into thin strips (discard the seeds). Heat oil in wok or large skillet over high heat. Add garlic and stir until golden brown, about 10 seconds. Add 0.5 cup of basil and the chilies and stir-fry just until basil wilts, about 1 minute. Add chicken and stir-fry about 3 minutes. Add nuoc mam, water and sugar and stir-fry until sauce bubbles and thickens slightly, about 2 minutes. Add remaining 0.25 cup of basil and stir-fry until just wilted, about 5 seconds. Serve immediately with steamed rice...