01 - Bring a large pot of salted water to a boil. Cook the pasta according to package instructions until al dente. Reserve ½ cup of pasta water, then drain and set aside.
02 - While the pasta cooks, heat the butter and olive oil in a large skillet over medium heat. Add the mushrooms and cook for 5–7 minutes, stirring occasionally, until golden and softened.
03 - Add the garlic and cook for 1 minute until fragrant.
04 - Reduce the heat to low. Pour in the heavy cream, Parmesan, and a splash of reserved pasta water. Stir well and simmer for 2–3 minutes until slightly thickened.
05 - Add the cooked pasta to the skillet and toss to coat in the sauce. Drizzle with truffle oil and season with salt and pepper to taste. Add more pasta water if needed for a silky sauce.
06 - Divide between two warm plates. Garnish with extra Parmesan, parsley, and shaved truffle if desired.