Place linguine, mushrooms, water, cream cheese (or mascarpone), pesto, heavy cream, and garlic in a large pan or skillet with high sides.
16 ounce(s) linguine, 8 ounce(s) mushrooms, 5 cups water, 4 ounce(s) mascarpone, ½ cup basil pesto, ½ cup heavy cream, 4 garlic cloves