Clean the mushrooms, remove the stems. Chop stalks and set aside. Drizzle the mushrooms with a few drops of lemon juice, white wine and Worchester sauce and season with salt and pepper.
Finely dice the bacon and leave it in a pan. Add the finely chopped onion and garlic as well as the chopped mushroom stalks and sweat with them. Clean the spinach, roughly chop it and add to the bacon. Take the pan off the fire. Mix in the cream cheese and season with a little lemon juice, white wine and Worchester sauce. Pour the mixture onto the mushrooms.
Grill variant: Place aluminum foil on the grill plate and brush with olive oil. Add the mushrooms and grill. Put the raclette cheese in a pan and pour the warm, liquid cheese over the mushrooms.
Oven variant: Put aluminum foil in ovenproof form as above and brush with olive oil.