Brown the mince with the onion and, when cooked through, stir in the pasta sauce and herbs.
Mix the cream cheese, curd cheese and sour cream until smooth.
Cook the spaghetti as directed on the packet and drain.
In an oiled ovenproof dish of about 3 litres, layer half the spaghetti, the cheese mixture, the rest of the spaghetti and finally the meat sauce; mix the breadcrumbs with the Parmesan and scatter over the top.
Bake for 30 minutes until bubbling and heated through.