Preheat Oven: Set your oven to 180°C (356°F).
Prepare Mushrooms: Place the sliced mushrooms on a baking sheet. Sprinkle with thyme, salt, and pepper. Drizzle with olive oil and toss to coat evenly.
Add Cream Cheese and Garlic: Dot the cream cheese around the mushrooms. Place the whole garlic bulb, cut side up, on the baking sheet. Drizzle the garlic with a bit of olive oil.
Bake: Cover the baking sheet with aluminium foil. Bake for 30-40 minutes, until the garlic is soft and the mushrooms are tender.
Cook the Pasta: While the mushrooms and garlic are baking, cook the pasta according to the package instructions. Ensure it's ready when the mushrooms are done.
Combine Everything: After baking, squeeze the roasted garlic cloves into a bowl and mash them. Add the garlic, baby spinach, and cooked pasta to the baking sheet with mushrooms. Toss everything well to combine.
Serve and Enjoy: Serve the warm dish and enjoy each delicious bite!