Heat half the oil in a large heavy bottomed frying pan and when hot add the sliced chicken. Allow the chicken to whiten all around, frequently turning the pieces to ensure even cooking. When you cannot see any more pink chicken add the chilli powder, smoked paprika, and black pepper. Mix around with the chicken and cook for a further 3-4 minutes on a medium heat, stirring frequently. The chicken should take on some of the colour of the paprika.