Arrange kale in a steamer basket over boiling water; cover and steam 2 minutes. Drain. Remove thick stems, and cut leaves into thin strips; set aside.
Cook pasta according to package directions; drain and set aside.
Remove and discard casings from sausage. Cook sausage in a Dutch oven over medium heat, stirring until it crumbles and is no longer pink; drain.
Add onion to sausage in Dutch oven, and sauté 5 minutes. Add garlic, and sauté 1 minute. Add vinegar, and cook 3 minutes. Add chicken broth and kale; cook 5 minutes. Stir in basil and next 3 ingredients; cook 1 minute. Stir in pine nuts, pasta, and feta cheese; cook until thoroughly heated. Serve immediately.
*1 (6-ounce) package fresh baby spinach may be substituted for kale. Omit steaming procedure.