Dice potatoes into 1cm cubes, dice chicken to desired size.
Mix the soy sauce and curry powder and a dash of pepper and marinate the chicken in that as you cook the potatoes.
Heat oil in pan, fry potatoes till cooked for about 10-15 minutes, stirring constantly so that the potatoes don't stick to the pan. Stir in chillies when potatoes are almost done, fry till fragrant.
Add in chicken when potatoes are cooked, stir in 3 tbsps curry powder and 4 tbsps of water or more if too dry.
Cook till the chicken is done - another 5-7 minutes.