Place the diced chicken in a bowl and mix with the italian herbs.
Place a large frying pan over medium–high heat. Add 1 tablespoon of the olive oil and cook the chicken for 4–5 minutes each side. Remove and set aside.
Place the pan back over medium–high heat. Add the remaining tablespoon of olive oil and the butter and let it heat. Add the onion and garlic and cook, stirring, for 2–3 minutes. Stir through the water or stock and pasta. Turn the heat down, cover with the lid and simmer for 5 minutes.
Remove the lid and stir through the cream. Add the broccoli and mix well. Place the lid back on and cook for about 5 minutes or until the pasta is al dente and the broccoli is just cooked.
Add the chicken, pesto and grated parmesan and stir through. Season well with salt and pepper.