Season the chicken breasts with salt, pepper and a little Cajun seasoning, then toss them in plain flour.
Melt the butter with the oil in a frying pan over a medium heat and fry the chicken until golden on both sides and cooked through.Set the chicken aside on a plate, loosely covered with tin foil.
In the same pan, fry the onions and garlic until the onions are translucent.Add a little extra oil if needed.
Add the peppers and cook for a couple of minutes, then sprinkle over the Cajun seasoning and cook for a minute or so.
Add the tomato purée and stir it in well, then pour in the cream and the chopped tomatoes.
Let the sauce heat through for 5 minutes, then add the parmesan.*Meanwhile, cook your pasta according to the packet instructions.
Let the sauce simmer for a further couple of minutes and season to taste with salt and pepper.
Return the chicken to the pan and let it warm through while the pasta finishes cooking.
Drain the pasta and divide it between 4 deep plates. Top with the chicken and plenty of sauce – you can slice the chicken before laying it on top if you like.
Scatter over some finely chopped fresh herbs and serve with a little extra parmesan on the side, if you like.