Season chicken pieces with salt and pepper.
In a large skillet over medium-high heat, heat oil and curry powder for two minutes.
Stir in onions and garlic, and cook for an additional minute.
Add chicken to the skillet, tossing lightly to coat with curry oil.
Reduce heat to medium, and cook for 7 to 10 minutes, or until chicken is no longer pink in the center and juices run clear.
Pour coconut milk, diced tomatoes, tomato sauce, and sugar into the pan, and stir to combine.
Cover and simmer, stirring occasionally, for approximately 30 to 40 minutes.
Serve hot, accompanied by rice and vegetables if desired.
Enjoy the rich and flavorful taste of this Coconut Curry Chicken, perfect for a cozy dinner at home with family or friends.