- Cook the pasta: Fill a large pot with salted water and bring to the boil. Add spaghetti and cook according to the direction on the package. While the spaghetti is boiling, reserve about 1/2 cup of pasta water. Drain the spaghetti and set aside.
- Make the spaghetti sauce: In a large pan over high heat, add oil, 1 tablespoon butter and garlic. Cook for 2 minutes and add the mushrooms and cook for 3 minutes. Add the shallots and cook for 2 minutes. Add half of the parsley and mix well.
- Add the spaghetti: Add the spaghetti to the pan and cook for 1 minute.
- Add parsley and seasoning: Turn the heat to low and add the remaining chopped parsley. Mix well and add soy sauce, butter and sake. Mix well again, making sure all the pasta is coated with all the ingredients.
- Serve: Serve with fresh parmesan.
Optional: Add freshly ground black pepper and a little bit of the pasta water to add richness to the sauce.