Directions

1. 1

   Fill a large pot with water to about 2 inches depth and bring to a rolling boil. Add salt generously (approximately 1 tablespoon per gallon of water).

2. 2

   While the water heats, trim the mushrooms and slice or shred them into bite-sized pieces.

3. 3

   Add the spaghetti to the boiling salted water and cook for 1 minute less than the package directions indicate.

4. 4

   In a separate frying pan over medium heat, warm the virgin olive oil. Add the chopped garlic and sauté, stirring occasionally, until fragrant and beginning to soften but not browning (about 1 minute).

5. 5

   Add the prepared mushrooms to the pan with the garlic. Sauté over medium-high heat, stirring frequently, until the mushrooms are wilted and beginning to brown on the edges. If needed, add a splash more olive oil to ensure even browning. Season with a pinch of salt and black pepper to taste.

6. 6

   When the pasta is nearly done and the mushrooms have browned, reduce the heat under the mushroom pan to medium-low. Add the unsalted butter and allow it to melt into the mushrooms, stirring gently.

7. 7

   Pour the soy sauce into the pan and add a ladle of starchy pasta water. Stir vigorously for about 30 seconds to emulsify the butter with the soy sauce and water, creating a silky sauce.

8. 8

   Using tongs or a slotted spoon, transfer the cooked spaghetti directly from the pot to the mushroom pan. Toss the pasta vigorously with the butter-shoyu mixture, adding more pasta water a little at a time as the sauce is absorbed, until the noodles are coated in a thin, creamy layer and reach your desired tenderness.

9. 9

   Divide the pasta between two bowls, garnish generously with fresh chopped parsley, and serve immediately while hot.