Cut the sausage lengthwise into quarters. Slice into 1/4-inch pieces. In a large skillet, cook leek and garlic in hot olive oil until leek is tender. Stir in sausage, chicken broth, and roasted peppers. Bring to boiling; reduce heat. Add spinach. Cook, stirring frequently, for 1 to 2 minutes or just until spinach starts to wilt. Remove from heat.
Meanwhile, cook the pasta according to package directions, omitting any oil or salt; drain. Return pasta to saucepan. Add spinach mixture, basil, Parmesan cheese, and black pepper. Toss to coat. Serve immediately. Makes 4 main-dish servings.