How to Make It
Cook pasta according to package directions, omitting salt and fat. Drain in a colander over a bowl, reserving 1/3 cup cooking liquid.
Heat a large skillet over medium-high heat. Add oil; swirl to coat. Add onion; sauté 3 minutes or until tender. Add garlic and mushrooms; cook 8 minutes or until mushrooms are browned. Add stock and salt; bring to a boil. Reduce heat, and simmer 5 minutes or until liquid is reduced by half. Stir in 1/3 cup reserved cooking liquid, dill, butter, rind, vinegar, and pepper. Add pasta; toss to coat. Place 1 1/4 cups pasta mixture in each of 4 bowls. Top each serving with 1 tablespoon ricotta cheese and 1 tablespoon Parmesan cheese.