Bring a large pot of salted water to a boil. Add the fettuccine and cook according to package instructions until al dente. Reserve 1 cup of pasta water, then drain the pasta.

Set the pasta aside.

In a skillet over medium heat, melt the butter. Continue cooking until it turns golden brown and develops a nutty aroma, about 5-7 minutes.

Add the minced garlic and sauté for 1 minute until fragrant.

Add the sliced mushrooms and cook until they are browned and tender, about 5-7 minutes.

Stir in the thyme, parsley, salt, and pepper.

Add the cooked pasta to the skillet with the brown butter sauce. Toss to combine, adding reserved pasta water as needed to create a silky sauce.

Serve immediately, topped with grated Parmesan cheese.