Soak dried Funghi Porcini Mushrooms in boiling-hot water for about 15-20 minutes. Remove mushrooms and finely slice, reserving the soaking liquid.
Melt 1 tablespoon of butter in a large skillet over medium heat.
Sauté fresh mushrooms with garlic until the water that the mushrooms give off evaporates – around 5 minutes.
Add chopped soaked mushrooms and remaining butter, stir until melted – around 30 seconds.
Add reserved mushroom-soaking liquid and simmer for 1 minute.
Add drained pasta to mushrooms in skillet, cooking over moderately high heat. Add lemon juice and zest, tossing and adding some reserved pasta-cooking liquid if necessary to lightly coat. Season with salt and pepper to taste.