Heat the olive oil in a frying pan. Add the shallots and garlic and saute over a moderate heat for a few minutes until softened and golden. They must not brown. Add the field mushrooms and cook for a further 5 minutes. Stir in the porcini and their reserved liquor and boil rapidly for 5 minutes until syrupy.

Bring a large saucepan of water to the boil and cook the pasta according to the instructions on the packet. Drain and return the pasta to the saucepan. Add the mushrooms and toss well. Divide the pasta between 4 individual gratin dishes.

Turn the grill to high. Spread the breadcrumbs and pine nuts out on a baking tray and toast for about 2 minutes. Mix with the thyme and scatter the mixture over the pasta. Drizzle a little olive oil on top and pop the dishes under the grill until the topping is golden. Serve immediately.