Brush off any dirt from the mushrooms with a tea towel. Slice the button mushrooms thinly, tear the Oyster Mushrooms in thin strips and cut the portobello in small chunks.
Place the olive oil in a very hot frying pan, and add the mushrooms. Let them sauté, tossing once or twice, then add the garlic and a pinch of salt, the salt will bring out the flavour of the mushrooms, almost right away, continue to sauté until the mushrooms are tender, tossing regularly. Then turn off the heat and squeeze in the lemon juice. Toss and season, to taste.
Meanwhile, cook the pasta in boiling, salted water until al dente. Drain and add to the mushrooms, with some of the Parmigiano cheese, the sage leaves and butter. Toss well to ensure the pasta is well coated, place in your favourite pasta bowls, garnish with some of the mushrooms and the buttery goodness from the bottom of the pot, sprinkle the remaining Parmigiano, a good grinding of fresh black pepper and a swish of the extra virgin olive oil