Penne with chorizo and cream

450g penne

1 chorizo sausage 

25g butter 

1 tsp fresh rosemary, finely chopped 

2 tins of chopped tomatoes, 

salt

freshly ground pepper

sugar 

pinch of crushed chillies 

175ml cream 

2 tbsp flat parsley, finely chopped

4 tbsp Parmesan, freshly grated