Grill the frozen sausages and cook the pasta according to packet instructions.
Slice the cooked sausages and set aside. Heat the oil in a large frying pan and add the peppers. Fry for 5 minutes until soft.
Add the sliced sausages, pour over the stock and cook for 2-3 minutes. Add the lemon zest and juice and the half fat crème fraîche. Cook over a low heat for a further 3 minutes until thickened slightly. Drain the pasta and return to the pan. Stir the parsley through the creamy sausage sauce.
Add the pasta and toss through. Season with black pepper and serve immediately.