Prepare your ingredients: Pre-cook the potatoes in a bowl covered with water in the microwave (don’t cook them too done, since they will finish cooking with the main dish later).Cut boneless, chicken breast into thin strips. Wash and cut onions into cubes.Separate all the pieces.
In a wok on medium heat add oil and curry paste. Add 1/3 of the coconut milk. Stir until it forms a thin gravy.
Add chicken, galangal, lime leaves. Cook for about 5 minute.
Turn the heat to high, add the rest of the coconut milk, potatoes and onions,fish sauce, sugar, and mix well. Set to boil for about 2 minutes.