Warm 1 tbsp olive oil over a medium heat. Add the pieces of sausage to the pan and gently stir them for 4 minutes making sure you turn them over halfway through. Sprinkle 1 tsp of the smoked paprika, ½ tsp of the fennel and ½ tsp of the cayenne pepper into the pan and stir the sausage pieces for a further 2 minutes. Take the pieces of sausage out of the pan, put them on a plate and set them to one side.
Run the pan under a cold tap to clean out the oil and spices, Add the red onion to the pan, sprinkle a pinch of salt into the pan and stir for 5-7 minutes. Add the garlic to the pan and stir for 1 minute. Add the red peppers to the pan and stir for 3 minutes. Sprinkle the remaining spices into the pan and stir for 30 seconds.
Add the tomato puree to the pan and stir for 30 seconds, pour the chopped tomatoes into the pan, stir them around so they’re well mixed. Half fill one of the tomato cartons with water, pour it into the pan, turn the heat down and leave to simmer for 10 minutes.
Whilst the sauce is simmering, put the saucepan on the stove, add the pasta to the saucepan and cook for 9 minutes until cooked but slightly al dente. Pour the pasta into the tomato sauce and stir it so it’s completely covered, then add the sausage pieces and stir in.