Bring a large pot of salted water to boil. Cook pasta according to package instructions until al dente. Remember to reserve 1/4 cup of pasta water before draining.

While the pasta cooks, heat olive oil in a large skillet over medium-high heat. Add mushrooms and cook until golden brown and their moisture has evaporated (about 8-10 minutes). Season with salt and pepper, then transfer to a plate.

In the same skillet, melt 2 tablespoons of butter. Add minced garlic and sauté until fragrant, about 1 minute.

Reduce heat to medium-low. Add heavy cream and remaining butter, stirring constantly until butter melts completely.

Gradually stir in the Parmesan cheese until smooth and creamy. If the sauce seems too thick, add reserved pasta water a little at a time.

Return mushrooms to the skillet and add the cooked pasta. Toss everything together until well combined and pasta is evenly coated.

Sprinkle with fresh thyme leaves and additional Parmesan if desired. Serve immediately.