Choose a new cookbook worth up to £28 when you subscribe to our magazine.
Preheat the oven to 200C/Gas 6/fan oven 180C. In a large bowl, mix together the mustard, oil, Worcestershire sauce and garlic, then season with salt and freshly ground black pepper.
Add the mushrooms to the mixture and toss well to coat them evenly. (You can do this ahead and let them marinate while you prepare the rest of the meal.) Place them stalk-side up in a roasting tin and sprinkle over the paprika. Bake for 8-10 minutes.
Divide the salad leaves between four serving plates. Put two mushrooms on each plate and spoon over the juices. Serve straight away, with French or crusty bread.