1 Trim the mushrooms with a soft brush or cloth. Break off stems gently. Peel the garlic and chop finely.
2 Trim spinach, rinse and spin dry.
3 Heat 2 tablespoons oil in a skillet, add the mushrooms and fry on each side for 2-3 minutes. Season with salt and pepper and remove from the skillet. Lay mushrooms with the open side up in a baking dish.
4 Add the remaining oil to the skillet. Sauté garlic briefly. Add spinach and cook while turning so that it softens slightly, but is still al dente, about 1 minute.
5 Stir in Marsala and simmer briefly. Season with salt and pepper.
6 Fill the mushrooms with the spinach mixture.
7 Crumble the cheese over the mushrooms and bake in preheated oven at 200°C (fan 180°C, gas mark 3) (approximately 400°F/convection 350°F) on the bottom rack for 10 minutes.