Bring a pot of generously salted water to a boil. Cook pasta till al dente. Drain and return to pot.
In a large skillet, melt butter over medium heat. Add mushrooms, cook for 3-5 min. Add the rest of the butter, garlic, sun dried tomatoes, and spinach cook until wilted. Add the cream and parmesan-reggiano cheese, mix till cheese has melted and the sauce starts to simmer. Salt and pepper to taste.