Prepare the chicken pieces by removing the skin, rinsing under cold water and patting dry with paper towels. Season chicken pieces with salt and pepper. Set aside.

Heat oil in a pan over medium high heat. Add garlic, onion and ginger and sauté for 2 minutes, or until onion has softened.

Add chicken pieces and sauté for 4 minutes or until browned and no longer pink.

Add fish sauce and stir to combine flavor. Add water, bring mixture to a boil, lower heat to medium, cover with a lid and let simmer for 20 minutes.

Remove lid and continue to simmer for another 10 minutes or until chicken meat is tender. Stir in spinach or pepper leaves. Cover and remove from heat.

Serve with steamed rice.