I start by sautéing the chicken which adds great flavour. However, I then remove it from the pan until I am ready to poach it in chicken stock. The trick with chicken breast is not to over cook it and also when poaching, do so gently at a simmer - no rapid boil needed here! Remember, cooking times do vary depending on the size and thickness of the chicken breasts you are using. If the chicken looks to be ready before the potatoes and other vegetables have cooked through, simply remove it from the pan and set aside. You can then add the chicken back into the stock to warm through just before serving. This is the best tip for not overcooking and results in moist and juicy chicken.