Preheat the oven to 200°C/gas mark 6. In a large ovenproof pan, heat the oil and cook the bacon for 5 minutes until crispy. Remove and reserve for later.
Add the onion, courgette and aubergine to the pan and fry for 5 minutes. Then add the tomatoes, garlic, chilli, passata, chicken stock cube and 50ml water. Bring to the boil, then reduce the heat and simmer for another 5 minutes.
Add the chicken thigh fillets, mixed herbs, the reserved bacon and half the parsley. Stir to coat the chicken in sauce and cook for 30 minutes in the oven. Remove from the oven and serve straight away garnished with the remaining parsley and seasoned with freshly ground black pepper.