In a 4-quart Dutch oven, bring the 8 cups water and 2 teaspoons of the salt to boiling. Place mushrooms in a small bowl; add 1 cup of the boiling water. Let stand for 15 minutes.
Meanwhile, add escarole or spinach to the remaining boiling water. Return water to boiling; immediately drain greens in a colander and rinse with cold water. Drain well, pressing out extra liquid; coarsely chop greens and set aside. Drain mushrooms, reserving 2 tablespoons of the liquid. Chop the mushrooms; set mushrooms and liquid aside.
In a large skillet cook, sausage, onion, garlic, and sage over medium heat until meat is browned, stirring to break up sausage. Drain off fat. Stir in wine and reserved mushroom liquid. Bring to boiling; reduce heat. Simmer, uncovered, about 7 minutes or until most of the liquid is evaporated. Add broth, marinara sauce, parsley, oil, pepper, and remaining 1/4 teaspoon sea salt. Bring to boiling; reduce heat. Simmer, uncovered, for 2 minutes.
Meanwhile, cook pasta in the Dutch oven according to package directions using fresh water. Reserve 1/4 cup pasta water and drain the pasta. Add pasta water, mushrooms, and cooked greens to pork mixture. Heat through; spoon over cooked pasta. Toss before serving. Top with shaved Parmesan cheese. Makes 4 to 6 main-dish servings.