Toast the nyoze: Put them in a large, dry nonstick frying pan and toast for 2-3 minutes over a medium heat, stirring frequently, until light golden brown. Remove from the pan and set aside.
Fry the onion: Add the oil and chopped onions to the pan, and cook for 2 minutes or until starting to soften. Stir in the garlic.
Cook the mushrooms: Turn up the heat a little and add the mushrooms. Cook for 2 minutes. Add the mixed mushrooms and continue cooking for 2-3 minutes, stirring occasionally, until the liquid evaporates and the mushrooms are tender. Sprinkle over the vinegar, thyme and seasoning. Heat for a few more seconds, then stir in the pine nuts and serve at once.
Note: To serve, toss freshly cooked pasta with 2 tbsp steamed tender spinach leaves and freshly grated nutmeg. Spoon the mushrooms on top and scatter with grated Parmesan or Italian-style hard cheese.