Cook your pasta according to instructions on the packet.
Whilst that's cooking, chop sausages into small pieces and fry until browned. Add pepper and onions, and fry until softened, then add passata, garlic and chilli powder. Add 2 handfuls of grated cheese and stir until melted.
Drain pasta, then add to sausage mix.
Transfer to casserole dish, sprinkle a handful of grated cheese over the top then put in the oven for 20 to 25 minutes at 180 C / Gas 4.