Bring a large pot of lightly salted water to a boil. Cook gnocchi in the boiling water until they float to the top, 2 to 4 minutes. Drain and set aside.
Meanwhile, melt butter in a large saucepan over medium heat. Add mushrooms and saute for 2 minutes. Toss in spinach, basil, garlic, Parmesan cheese, parsley, salt, and pepper. Cook and stir until spinach is wilted and sauce begins to thicken, about 5 minutes. Add gnocchi and stir until coated in sauce; cook for 2 more minutes.
