Heat olive oil in skillet or dutch oven.
Sauté onions and peppers until translucent, about 4 minutes. Remove from skillet and set aside.
Add chicken to skillet and cook until cooked through, about 10 minutes. Season with salt and pepper. Remove and set aside.
Add garlic, ginger, and red thai curry paste to pot. Cook for 1-2 minutes.
Add chicken and vegetables back to skillet. Add coconut milk, fish sauce, and brown sugar. Stir to combine.
Reduce heat to low. Add cornstarch and water mixture and stir. Cook over low heat for about 5 minutes. Serve with white rice. Enjoy :)