1. Melt 115g (4 oz) of butter in a large skillet over medium heat, which is equivalent to 175°C (350°F) on your stovetop.

2. Add 1 large onion, chopped, to the skillet and cook until softened, about 5 minutes.

3. Next, add 2-3 cloves of garlic, minced, and cook for an additional minute, stirring occasionally to prevent burning.

4. Pour in 120ml (1/2 cup) of white wine and 120ml (1/2 cup) of water into the skillet, bringing to a boil. Then reduce the heat to low and simmer until the liquid has reduced by half, about 5 minutes.

5. Stir in 240ml (1 cup) of heavy cream and bring the mixture to a simmer. Cook until slightly thickened, about 2-3 minutes.

6. Season the mixture with salt, pepper, and a few drops of truffle oil to taste.

7. While the sauce is cooking, cook 225g (8 oz) of fresh pasta according to package instructions until al dente, which should take about 3-5 minutes depending on the type of pasta. Drain and set aside.

8. Add 115g (4 oz) of chopped wild mushrooms to the skillet and cook until they release their liquid and start to brown, about 3-4 minutes. If desired, stir in 1 tablespoon of flour and cook for an additional minute.

9. Combine the cooked pasta and mushroom mixture, tossing to combine.

10. Season with additional salt, pepper, and truffle oil if desired.

11. Serve immediately, garnished with chopped fresh parsley.