Preheat the oven to 400. Fold a piece of parchment paper in half and set one side of it on a baking tray.
Place the mushrooms onto the paper and top with the tofu. Top with onions, tomatoes and sprigs of thyme.
Whisk together the oil and vinegar and drizzle over the top. Season with salt and pepper.
Fold up the other side of the parchment and working from one end tightly fold the open edge to form a seal.
Bake for 30 minutes. Enjoy!