Grate Parmesan, chop garlic and parsley, cut champignons into thin slices.
Heat a frying pan with vegetable oil and fry the garlic and thyme, then add the mushrooms and fry until all the liquid has evaporated. Then add salt, pepper and parsley.
Mix fried mushrooms with grated cheese.
Place the filling on the bread in layers: bread, chicken, mushrooms, bread. Then bake the sandwiches in a sandwich maker for a couple of minutes.