Bring a large pot of water to boil. Heat a large sauté pan over medium-high heat. Add olive oil, sausage, and onions and cook until sausage pieces are browned and onion is caramelized; remove from pan. In the same pan add the kale and cook until wilted and tender, adding a little water if necessary. While the kale is cooking, add the pasta to the boiling water. When the kale is cooked, add the sausage, onions, and tomatoes to the pan. Taste; season with salt and pepper. When the pasta is cooked al dente, drain and reserve some of the cooking water. Add pasta to the sauté pan; toss pasta with vegetables and sausage, adding a little of the pasta cooking water if the pasta looks a little dry. Sprinkle with parsley and toss again. Place pasta onto 4 serving dishes and serve immediately, passing the Parmesan cheese to sprinkle on top. Makes 4 servings.
Approximate Nutrient Analysis per serving (not including salt to taste):
300 calories, 9 g fat, 1.5 g saturated fat, 0 mg cholesterol, 85 mg sodium, 43 g carbohydrate, 11 g fiber, 5 g sugar, 15 g protein