Heat 1 tablespoon of the oil in a large frying pan over medium heat.
Sauté the onion and red pepper until it begins to soften.
Meanwhile, put the flour, curry powder, salt and pepper in a large plastic bag. Add the chicken breasts, seal the bag and shake until the chicken is coated in the floury mixture. You may need to do this in batches.
When the vegetables have begun to soften, remove them from the frying pan and keep warm.
Add the remaining tablespoon of vegetable oil to the pan and when it has heated up, add the flour and spice coated chicken breasts.
Cook the chicken for about five minutes on each side, until it has begun to take on a bit of a golden colour.
Mix together the mango chutney and ¼ cup of the chicken stock.
Turn the heat up on the chicken breasts and add the chutney and stock, allowing it to bubble up around the chicken breasts.
Return the heat to medium and return the onions and peppers to the pan with the chicken. Continue to cook, turning the chicken once or twice, until the meat is cooked through with an internal temperature of 165°F and no pink remains inside.
Check the sauce. If it is too thick you can add a the remaining ¼ cup of chicken stock, a bit at a time, until the desired consistency is reached.
Carefully taste a bit of the sauce (it will be hot) and add more pepper to taste if necessary.
Serve the chicken with rice, a green vegetable and some warm Nan bread.