Preheat the oven to 200°C, 400°F, Gas Mark 6.Lay the mushrooms on a large baking tray and sprinkle with the onions, garlic and thyme. Slice the Taleggio thinly and use to top the mushrooms. Combine the breadcrumbs with the parsley in a bowl and sprinkle over. Bake for 15-20 minutes or until breadcrumbs are brown and the mushrooms are cooked through. Serve with a rocket salad dressed with lemon juice and Petrolo oil. Alternatively, serve the baked mushrooms on toasted ciabatta